| All names | Aban | Chrysanthemum segetum |
| All names | Adain-redynen | Pteridium aquilinum |
| All names | Aderyn corph | Taxodium distichum |
| All names | Aderyn-y-Cyrph | Taxodium distichum |
| All names | Aedorw | Hedera helix |
| All names | Aethnen | Populus tremula |
| All names | Aethnen Ddu | Populus nigra |
| All names | Aethnen Lwyd | Populus canescens |
| All names | Aethnen Wen | Populus alba |
| All names | Aethwydden | Populus tremula |
| All names | Afal Adda | Tamus communis |
| All names | Afal Agroed | Mespilus germanica |
| All names | Afal Daear | Aristolochia clematitis |
| All names | Afal Dreiniog | Datura stramonium |
| All names | Afal Tindwll | Mespilus germanica |
| All names | Afallen | Malus sylvestris |
| All names | Afalwydden | Malus sylvestris |
| All names | Afan | Rubus idaeus |
| All names | Afanen | Rubus idaeus |
| All names | Afanllwyn | Rubus idaeus |
| All names | Afans | Geum urbanum |
| All names | Afryn Coliog | Lolium temulentum |
| All names | Aith | Ulex minor |
| All names | Aith | Ulex europaeus |
| All names | Alan | Tussilago farfara |
| All names | Alan Bychan | Tussilago farfara |
| All names | Alan Mawr | Petasites hybridus |
| All names | Alannan | Asarum europaeum |
| All names | Alaw | Nymphaea alba |
| All names | Alaw Canada | Elodea canadensis |
| All names | Alaw Crewyll | Convallaria majalis |
| All names | Alaw Diosgo | Stratoides aloides |
| All names | Alaw Lleiaf | Hydrocharis morsus-ranae |
| All names | Aleluia | Oxalis acetosella |
| All names | Alisantr | Smyrnium olusatrum |
| All names | Almonwydd | Amygdalus communis |
| All names | Amdowellt | Elymus arenarius |
| All names | Amlaethai | Polygala vulgaris |
| All names | Amlaethai | Polygala |
| All names | Amrain | Hydrocotyle vulgaris |
| All names | Amranwen | Tripluerospermum maritimum agg. |
| All names | Amranwen | Matricaria recutita |
| All names | Amranwen Gyffredin | Matricaria recutita |
| All names | Amranwen Helen Lueddog | Meum athamanticum |
| All names | Amrhydlwyd | Erigeron acer |
| All names | Amrhydlwyd Rhuddlas | Erigeron acer |
| All names | Amrhydlwyd y Mynydd | Erigeron alpinus |
| All names | Andromeda | Andromeda polifolia |
| All names | Anfri | Adoxa moschatellina |
| All names | Archmain | Armeria maritima |
| All names | Arfog | Sisymbrium officinale |
| All names | Arfog Meddygol | Sisymbrium officinale |
| All names | Arian Cor | Rhinanthus minor |
| All names | Arian Gwion | Rhinanthus minor |
| All names | Arian Gwion Bach | Pedicularis palustris |
| All names | Arian y Gweirwyr | Rhinanthus minor |
| All names | Arianllys | Thalictrum alpinum |
| All names | Arianllys Bach | Thalictrum minus |
| All names | Arianllys Bychan | Thalictrum minus |
| All names | Arianllys Cyffredin | Thalictrum alpinum |
| All names | Arianllys Mawr | Thalictrum majus |
| All names | Arianllys Mwyaf | Thalictrum majus |
| All names | Arlladlys | Centaurium minus |
| All names | Artisiog Jerwsalem | Helianthus tuberosus |
| All names | Aspygan | Leucanthemum vulgare |
| All names | Astyllenllys | Plantago lanceolata |
| All names | Aur Bach y Gwanwyn | Ranunculus ficaria |
| All names | Aur yr ꤼ/TD> | Sinapis arvensis |
| All names | Bachgen Llwm | Leycestria formosa |
| All names | Bacsau'r Brain | Endymion nonscriptus |
| All names | Bacwn ac �/TD> | Lotus corniculatus |
| All names | Balchder Llundain | Saxifraga urbium x |
| All names | Balm | Melissa officinalis |
| All names | Balog | Pedicularis palustris |
| All names | Banadl | Cytisus scoparius |
| All names | Banadlen | Cytisus scoparius |
| All names | Banadlos | Genista tinctoria |
| All names | Banhadlen | Cytisus scoparius |
| All names | Banhadlen Aur | Genista tinctoria |
| All names | Banhadlen Bigog | Ruscus aculeatus |
| All names | Banhadlos | Genista tinctoria |
| All names | Banhalen | Cytisus scoparius |
| All names | Banhallen | Cytisus scoparius |
| All names | Bara Can a Llaeth | Stellaria holostea |
| All names | Bara Can a Llaeth | Cardamine pratensis |
| All names | Bara Can y Defaid | Plantago maritima |
| All names | Bara Can y Gwcw | Oxalis acetosella |
| All names | Bara'r Cythraul | Succisa pratensis |
| All names | Bara'r Gog | Oxalis acetosella |
| All names | Bara'r Hwch | Cyclamen hederifolium |
| All names | Barf y Gŵr Hen | Clematis vitalba |
| All names | Barf yr Afr | Tragopogon pratensis |
| All names | Barf yr Afr Fawr | Tragopogon pratensis |
| All names | Barf yr Afr Felen | Tragopogon pratensis |
| All names | Barf yr Afr Ruddlas | Tragopogon pratensis |
| All names | Barthlys | Parietaria judaica |
| All names | Baw-Mwci | Arctium lappa |
| All names | Bawm | Melissa officinalis |
| All names | Beatws | Beta vulgaris var. maritima |
| All names | Bedwen Chwerw | Eupatorium cannabinum |
| All names | Bedwen Gyffredin | Betula pubescens |
| All names | Beidiog Goch | Polygonum amphibium |
| All names | Beidiog Llwyd | Artemisia vulgaris |
| All names | Beidiog Rudd | Polygonum amphibium |
| All names | Beidog Las | Glechoma hederacea |
| All names | Beistonnell | Littorella uniflora |
| All names | Beistonnell Merllyn | Littorella uniflora |
| All names | Bela | Hyoscyamus niger |
| All names | Benedigeidlys | Geum urbanum |
| All names | Berfain Cyffredin | Arabidopsis thaliana |
| All names | Berllys | Anthriscus sylvestris |
| All names | Berw Taliesin | Sedum telephium |
| All names | Berw'r Gwyllt | Lepidium latifolium |
| All names | Berw'r Iâr | Polygonum arenastrum |
| All names | Berw'r Ieir | Polygonum arenastrum |
| All names | Berwr Caersalem | Sisymbrium irio |
| All names | Berwr Chwerw | Cardamine amara |
| All names | Berwr Ffrengig | Lepidium sativum |
| All names | Berwr Gardd | Lepidium sativum |
| All names | Berwr Melyn Blynyddol y Dŵr | Rorippa islandica |
| All names | Berwr Melyn Mwyaf y Dŵr | Rorippa amphibia |
| All names | Berwr Melyn Ymlusgol y Dŵr | Rorippa sylvestris |
| All names | Berwr Môn a Manaw | Rynchosinapis monensis |
| All names | Berwr y Cerrig | Cardaminopsis petraea |
| All names | Berwr y Dŵr | Nasturtium officinale |
| All names | Berwr y Fagwyr | Arabidopsis thaliana |
| All names | Berwr y Fam | Descurainia sophia |
| All names | Berwr y Ffynhonnau | Nasturtium officinale |
| All names | Berwr y Gaeaf | Barbarea vulgaris |
| All names | Berwr y Graig | Arabis hirsuta |
| All names | Berwr y Meysydd | Cardamine hirsuta |
| All names | Berwr y Moch | Coronopus squamatus |
| All names | Berwr y Torlennydd | Rorippa amphibia |
| All names | Berwr yr Ardd | Lepidium sativum |
| All names | Berwy Caersalem | Sisymbrium irio |
| All names | Beryn | Iberis amara |
| All names | Beryn Chwerw | Iberis amara |
| All names | Beryn Coesnoeth | Teesdalia nudicaulis |
| All names | Betys | Festuca richardsonii |
| All names | Betys Gwyllt | Festuca richardsonii |
| All names | Betysen | Beta vulgaris var. maritima |
| All names | Betysen | Festuca richardsonii |
| All names | Bidawglys | Lobelia dortmanna |
| All names | Bidoglys | Lobelia dortmanna |
| All names | Bidoglys Chwerw | Lobelia dortmanna |
| All names | Bidoglys Dyfrdrig | Lobelia dortmanna |
| All names | Bidoglys y Dŵr | Lobelia dortmanna |
| All names | Bilwg yr ꤼ/TD> | Agrostemma githago |
| All names | Biwlith | Melampyrum |
| All names | Biwlys | Melampyrum pratense |
| All names | Blaen y Conyn ar y Mêl | Agrimonia eupatoria |
| All names | Blaen y Gwayw Lleiaf | Ranunculus flammula |
| All names | Blaen y Gwayw Mwyaf | Ranunculus lingua |
| All names | Blaen yr Iwrch | Mercurialis |
| All names | Bleidd-dag | Aconitum napellus |
| All names | Bleidd-drem | Lychnis viscaria |
| All names | Blewgeirch | Avena strigosa |
| All names | Blewog | Verbascum thapsus |
| All names | Blewynnog | Hieracium pilosella |
| All names | Blewynnog | Hieracium |
| All names | Blewynnog | Hieracium pilosella |
| All names | Blewynnog | Hieracium vulgatum |
| All names | Bliw | Daphne mezereon |
| All names | Bliwlys | Daphne mezereon |
| All names | Bliwyn | Daphne mezereon |
| All names | Blodau Mihangel | Gentiana pneumonanthe |
| All names | Blodau'r Brain | Lychnis flos-cuculi |
| All names | Blodau'r Brenin | Paeonia mascula |
| All names | Blodau'r Cedig Bychain | Cardamine pratensis |
| All names | Blodau'r Domen | Chenopodium album |
| All names | Blodau'r Gethlydd | Cardamine pratensis |
| All names | Blodau'r Gog | Cardamine pratensis |
| All names | Blodau'r Gwcw | Cardamine pratensis |
| All names | Blodau'r Haul | Helianthus annuus |
| All names | Blodau'r Mêl | Filipendula ulmaria |
| All names | Blodau'r Nadroedd | Silene dioica |
| All names | Blodau'r Neidr | Silene dioica |
| All names | Blodeuyn Wyneb Mair | Viola tricolor |
| All names | Blodyn Crach | Silene dioica |
| All names | Blodyn Glas | Myosotis palustris |
| All names | Blodyn Glas | Myosotis arvensis |
| All names | Blodyn Llefrith | Cardamine pratensis |
| All names | Blodyn Llo Bach | Cardamine pratensis |
| All names | Blodyn Llo Mawr | Leucanthemum vulgare |
| All names | Blodyn Llyffant | Pedicularis sylvatica |
| All names | Blodyn Neidr | Silene dioica |
| All names | Blodyn Taranau | Silene dioica |
| All names | Blodyn y Fagwyr | Cheiranthus cheiri |
| All names | Blodyn y Frân | Lychnis flos-cuculi |
| All names | Blodyn y Gog | Cardamine pratensis |
| All names | Blodyn y Gwynt | Anemone nemorosa |
| All names | Blodyn y Mwnci | Mimulus guttatus |
| All names | Blodyn y Pasg | Pulsatilla vulgaris |
| All names | Blodyn Ymenyn | Ranunculus bulbosus |
| All names | Blodyn Ymeynyn | Ranunculus acris |
| All names | Bloneg y Ddaear | Bryonia dioica |
| All names | Bocys | Buxus sempervirens |
| All names | Bogail Gwener | Umbilicus rupestris |
| All names | Bogail y Bugail | Umbilicus rupestris |
| All names | Bogail y Forwyn | Umbilicus rupestris |
| All names | Boglynnon | Eryngium maritimum |
| All names | Boglynnon | Eryngium planum |
| All names | Boglynnon Arfor | Eryngium maritimum |
| All names | Boled Olwen | Calystegia sepium |
| All names | Botasen y Gog | Endymion nonscriptus |
| All names | Botias y Gog | Endymion nonscriptus |
| All names | Brail | Rosa |
| All names | Braillu Albanaidd | Primula scotica |
| All names | Braillu Blodiog | Primula farinosa |
| All names | Brathlys | Anagallis arvensis |
| All names | Brathlys Gwryw | Anagallis arvensis |
| All names | Brechlys | Stellaria media |
| All names | Breichwellt y Coed | Brachypodium sylvaticum |
| All names | Breichwellt y Tŵr | Brachypodium pinnatum |
| All names | Breila | Rosa |
| All names | Breilylwyn | Rosa |
| All names | Brenhines y Weirglodd | Filipendula ulmaria |
| All names | Brenhinllys | Acinos arvensis |
| All names | Brenhinllys Gwyllt | Clinopodium vulgare |
| All names | Bresych | Brassica oleracea |
| All names | Bresych Gwyllt | Brassica oleracea |
| All names | Bresych Môn a Manaw | Rynchosinapis monensis |
| All names | Bresych y Cŵn | Mercurialis perennis |
| All names | Bresych y Cŵn Parhaus | Mercurialis perennis |
| All names | Bresych y Môr | Crambe maritima |
| All names | Bresych yr ꤼ/TD> | Brassica napus var. oleifera |
| All names | Breuwydd | Frangula alnus |
| All names | Brial | Parnassia palustris |
| All names | Brial y Gors | Parnassia palustris |
| All names | Briallu Cyffredin | Primula vulgaris |
| All names | Briallu Mair | Primula veris |
| All names | Briallu Mair Di-sawr | Primula eliator |
| All names | Briallu Mair Sawrus | Primula veris |
| All names | Briallu Tal | Primula eliator |
| All names | Briallu'r Dydd | Bellis perennis |
| All names | Brigau y twynau | Galium verum |
| All names | Briger t twynau | Galium verum |
| All names | Briger y Twynau | Galium verum |
| All names | Brigner Gwener | Adiantum capillus-veneris |
| All names | Brigner Gweno | Adiantum capillus-veneris |
| All names | Brigwellt | Aira praecox |
| All names | Brigwellt Arian | Aira caryophyllea |
| All names | Brigwellt Cribog | Koeleria gracilis |
| All names | Brigwellt Cudynnog | Deschampsia cespitosa |
| All names | Brigwellt Dyfrdrig | Catabrosa aquatica |
| All names | Brigwellt Gwyrgam Mynyddol | Deschampsia flexuosa |
| All names | Brigwellt Main | Deschampsia flexuosa |
| All names | Brigwellt Mawnog | Deschampsia cespitosa |
| All names | Brigwellt y Gwanwyn | Aira praecox |
| All names | Brigwlydd | Callitriche |
| All names | Brigwlydd Cynaeafol | Callitriche hermaphroditica |
| All names | Brigwlydd Gwanwynol | Callitriche palustris |
| All names | Brigwydd | Myosoton aquaticum |
| All names | Bril-lys Coraidd | Centunculus minima |
| All names | Brilys | Centunculus minima |
| All names | Britheg | Fritillaria meleagris |
| All names | Brithogen y Goedwig | Anemone nemorosa |
| All names | Briw'r March | Verbena officinalis |
| All names | Briweg | Sedum |
| All names | Briweg Blewog | Sedum villosum |
| All names | Briweg y Cerrig | Sedum anglicum |
| All names | Briwlys | Stachys |
| All names | Briwlys Blynyddol | Stachys annua |
| All names | Briwlys Tewbannog | Stachys germanica |
| All names | Briwlys y Goedwig | Stachys sylvatica |
| All names | Briwlys y Gors | Stachys palustris |
| All names | Briwlys y Taeog | Stachys palustris |
| All names | Briwlys yr Âr | Stachys arvensis |
| All names | Briwlys yr ꤼ/TD> | Stachys arvensis |
| All names | Briwydd | Galium palustre |
| All names | Briwydd Felen | Galium verum |
| All names | Briwydd Felen | Galium verum |
| All names | Briwydd Pêr | Galium odoratum |
| All names | Briwydd wen | Galium saxatile |
| All names | Briwydd Wen | Galium mollugo |
| All names | Briwydd y Fign | Galium uliginosum |
| All names | Briwydd y Gors | Galium palustre |
| All names | Bromwellt Hysb | Bromus sterilis |
| All names | Bromwellt llyfn | Bromus racemosus |
| All names | Bromwellt syth | Bromus erectus |
| All names | Bronwellt Masw | Bromus hordeaceus |
| All names | Bronwen | Matricaria recutita |
| All names | Bronwerth | Borago officinalis |
| All names | Bronwerth y Wiber | Echium vulgare |
| All names | Bronwst | Ranunculus ficaria |
| All names | Bronwys Melyn y Gwanwyn | Ranunculus ficaria |
| All names | Bronwyst | Ranunculus ficaria |
| All names | Bruesg | Ruscus aculeatus |
| All names | Brwynen | Juncus |
| All names | Brwynen Algron | Juncus bulbosus |
| All names | Brwynen Arfor | Juncus maritimus |
| All names | Brwynen Babwyr | Juncus effusus |
| All names | Brwynen Babwyr Bellennaidd | Juncus conglomeratus |
| All names | Brwynen Bellennaidd | Juncus conglomeratus |
| All names | Brwynen Droellgorun | Juncus squarrosus |
| All names | Brwynen Flewog y Maes | Luzula campestris |
| All names | Brwynen Flodeuog | Butomus umbellatus |
| All names | Brwynen Flodeuog | Butomus umbellatus |
| All names | Brwynen Flodfain | Juncus acutiflorus |
| All names | Brwynen Fwlbaidd | Juncus bulbosus |
| All names | Brwynen Galed | Juncus inflexus |
| All names | Brwynen Gerard | Juncus gerardii |
| All names | Brwynen Glymalog | Juncus articulatus |
| All names | Brwynen Glymog a Blodau Blaendwn | Juncus subnodulosus |
| All names | Brwynen Glymog a Blodau Blaenfain | Juncus acutiflorus |
| All names | Brwynen Glymog Glaergib | Juncus articulatus |
| All names | Brwynen Talgron | Juncus compressus |
| All names | Brwynen y Goedwig | Juncus acutiflorus |
| All names | Brwynen y Goedwig Fwyaf | Luzula sylvatica |
| All names | Brwynen y Llyffant | Juncus bufonius |
| All names | Brwysgedlys | Coriandrum sativum |
| All names | Brymlys | Mentha pulegium |
| All names | Brytwn | Artemisia campestris |
| All names | Brywydd Groes | Cruciata laevipes |
| All names | Bual | Ajuga reptans |
| All names | Bugeiles y Weirglodd | Filipendula ulmaria |
| All names | Buladd | Cicuta virosa |
| All names | Bulwg | Agrostemma githago |
| All names | Bulwg Rhufain | Agrostemma githago |
| All names | Bulwg yr ꤼ/TD> | Agrostemma githago |
| All names | Bumustl | Cicuta virosa |
| All names | Burnet | Sanguisorba minor |
| All names | Burnet Mawr | Sanguisorba officinalis |
| All names | Bustl y Ddaear | Centaurium minus |
| All names | Bwglos | Lychnis viscaria |
| All names | Bwglos y Wiber | Echium vulgare |
| All names | Bwltis | Nuphar lutea |
| All names | Bwltis | Nymphaea alba |
| All names | Bwtsias y Gog | Endymion nonscriptus |
| All names | Bwyd Hwyaid | Lemna trisulca |
| All names | Bwyd Hwyaid | Lemna minor |
| All names | Byddarllys | Sempervivum tectorum |
| All names | Byddon | Eupatorium cannabinum |
| All names | Byddon Chwerw | Eupatorium cannabinum |
| All names | Bydiog | Glechoma hederacea |
| All names | Bydiog Las | Glechoma hederacea |
| All names | Bydiog Lwyd | Artemisia vulgaris |
| All names | Bys y Blaidd | Lupinus micranthus |
| All names | Bysedd Cochion | Digitalis purpurea |
| All names | Bysedd Ellyllon | Digitalis purpurea |
| All names | Bysedd y Cŵn | Digitalis purpurea |
| All names | Bysedd yr Iâr | Raphanus raphanistrum |
| All names | Bysedd yr Iâr Arforol | Raphanus maritimus |
| All names | Bystwn y Fagwyr | Draba muralis |
| All names | Byswellt | Dactylis glomerata |
| All names | Byswellt Garwaidd | Dactylis glomerata |
| All names | Bywfyth | Sempervivum tectorum |
| All names | Bywfyth Leiaf | Sedum acre |
| All names | Bywi | Conopodium majus |
| All names | Bywlys | Sedum telephium |
| All names | Bywlys | Sedum |
| All names | Bywlys llydanddail | Sedum telephium |
| All names | Bywydog | Sedum reflexum |
| All names | Bywydog | Sedum |
| All names | Bywydog Boeth | Sedum acre |
| All names | Cabaits | Brassica oleracea |
| All names | Cabatsen | Brassica oleracea |
| All names | Cabets Gwyllt | Brassica oleracea |
| All names | Cacamwci | Arctium lappa |
| All names | Cacamwci Lleiaf | Xanthium strumarium |
| All names | Cadafarch | Sinapis arvensis |
| All names | Cadafarth | Sinapis arvensis |
| All names | Caineirian | Listera ovata |
| All names | Caineirian Gefell-lys | Listera ovata |
| All names | Caineirian Nydd-dro | Spiranthes spiralis |
| All names | Caineirian Nydd-droedig | Spiranthes spiralis |
| All names | Caineirian Troellog | Spiranthes spiralis |
| All names | Caineirian yr Ednogyn | Ophrys insectifera |
| All names | Cala'r Gethlydd | Arum maculatum |
| All names | Cala'r Mynach | Arum maculatum |
| All names | Calaf | Phragmites australis |
| All names | Caldrist lydanddail | Epipactis helleborine |
| All names | Caldrist Wen | Cephalanthera damasonium |
| All names | Caldrist y Banadl | Orobanche rapum-genistae |
| All names | Caldrist y Gors | Epipactis palustris |
| All names | Calfelfed | Typha latifolia |
| All names | Caliwlyn-y-Mêl | Agrimonia eupatoria |
| All names | Camamil | Anthemis nobilis |
| All names | Camined y Dŵr | Iris pseudacorus |
| All names | Camri | Anthemis nobilis |
| All names | Camri Cyffredin | Anthemis nobilis |
| All names | Camri Melyn | Anthemis tinctoria |
| All names | Camri'r Cŵm | Anthemis cotula |
| All names | Camri'r ꤼ/TD> | Anthemis arvensis |
| All names | Canclwm | Polygonum arenastrum |
| All names | Canclwyf | Lysimachia nummularia |
| All names | Candoll | Hypericum perforatum |
| All names | Canewin | Sedum telephium |
| All names | Canhanol | Parietaria judaica |
| All names | Cannwyl yr adar | Verbascum thapsus |
| All names | Cantafod | Parietaria judaica |
| All names | Canwen Ddu | Nardus stricta |
| All names | Canwraidd Goch | Polygonum amphibium |
| All names | Canwraidd Las | Glechoma hederacea |
| All names | Canwraidd Lwyd | Artemisia vulgaris |
| All names | Canwyllfrwynen | Juncus effusus |
| All names | Carddwy | Carum carvi |
| All names | Cardwy | Carum carvi |
| All names | Carllys Mawr | Tordylium maximum |
| All names | Carn Ebol y gerddi | Asarum europaeum |
| All names | Carn Ebol y Môr | Calystegia soldanella |
| All names | Carn yr Ebol | Tussilago farfara |
| All names | Carnedd | Senecio vulgaris |
| All names | Carnedd Felen | Senecio vulgaris |
| All names | Carnedd Felen | Senecio vulgaris |
| All names | Carnedd Felen Wryw | Senecio jacobaea |
| All names | Carpiog y Gors | Lychnis flos-cuculi |
| All names | Cartheig | Lapsana communis |
| All names | Cartheig Cyffredin | Lapsana communis |
| All names | Caru'n Ofer | Viola tricolor |
| All names | Carwas | Carum carvi |
| All names | Carwas Troellog | Carum verticillatum |
| All names | Carwlys | Tordylium maximum |
| All names | Carwlys Mawr | Tordylium maximum |
| All names | Carwy | Carum carvi |
| All names | Cas gan Arddwr | Ononis repens |
| All names | Cas gan Arddwr | Ononis spinosa |
| All names | Cas gan Bladurwr | Nardus stricta |
| All names | Cas gan Gythraul | Sorbus aucuparia |
| All names | Cas-gan-fursen | Cannabis sativa |
| All names | Cas-gan-Gythraul | Verbena officinalis |
| All names | Castanwydden | Castanea sativa |
| All names | Castanwydden y Meirch | Aesculus hippocastanum |
| All names | Caswenwyn | Succisa pratensis |
| All names | Cawen | Sparganium erectum |
| All names | Cawl | Brassica oleracea |
| All names | Cawl Gwyllt | Brassica oleracea |
| All names | Cawlen | Brassica oleracea |
| All names | Cawn Pensidan | Agrostis capillaris |
| All names | Cawnwellt | Phalaris arundinacea |
| All names | Cawnwen Benwen | Holcus lanatus |
| All names | Cecsen | Heracleum sphondylium |
| All names | Cedor y Wrach | Arctium lappa |
| All names | Cedowrach | Arctium lappa |
| All names | Cedowrach | Arctium minus |
| All names | Cedowrach Lleiaf | Arctium minus |
| All names | Cedowrach Mwyaf | Arctium lappa |
| All names | Cedowrach y Coed | Arctium nemorosum |
| All names | Cedowydd Cyffredin | Erigeron acer |
| All names | Cedowydd Cyffredin | Pulicaria dysenterica |
| All names | Cedowys Cyffredin | Pulicaria dysenterica |
| All names | Cedowys sugnol | Inula crithmoides |
| All names | Cedrwydden | Cedrus libani |
| All names | Cedrwydden Libanus | Cedrus libani |
| All names | Cedu du | Brassica nigra |
| All names | Cedu Gwyllt | Sinapis arvensis |
| All names | Cedu Gwyn | Sinapis alba |
| All names | Cedu'r Tywod | Diplotaxis muralis |
| All names | Cedw Du | Brassica nigra |
| All names | Cedw Gwyllt | Sinapis arvensis |
| All names | Cedw Gwyn | Sinapis alba |
| All names | Cedw'r Berth | Sisymbrium officinale |
| All names | Cegid | Conium maculatum |
| All names | Cegid Manddail y Dŵr | Oenanthe aquatica |
| All names | Cegid y Dŵr | Oenanthe crocata |
| All names | Cegiden | Conium maculatum |
| All names | Cegiden fenyw | Anthriscus sylvestris |
| All names | Cegiden Wen | Myrrhis odorata |
| All names | Cegyr | Conium maculatum |
| All names | Cegyr Mawr | Cicuta virosa |
| All names | Ceian | Dianthus |
| All names | Ceiliog Coch | Silene dioica |
| All names | Ceiliog y mynydd (m) | Lagarosiphon major |
| All names | Ceilion | Galium verum |
| All names | Ceilion | Galium verum |
| All names | Ceilys | Dianthus |
| All names | Ceineirian | Listera ovata |
| All names | Ceineirian Bach | Listera cordata |
| All names | Ceiniog y Gors | Hydrocotyle vulgaris |
| All names | Ceinioglys | Sibthorpia europaea |
| All names | Ceirchwellt Blewog | Helictotrichon pubescens |
| All names | Ceirchwellt Culddail | Helictotrichon pratensis |
| All names | Ceirchwellt Mânbluaidd | Helictotrichon pubescens |
| All names | Ceirchwellt Melyn | Trisetum flavescens |
| All names | Ceirchwellt Melynaidd | Trisetum flavescens |
| All names | Ceirios y Gŵr Drwg | Atropa belladonna |
| All names | Ceiriosen | Prunus cerasus |
| All names | Ceiriosen Ddu | Prunus avium |
| All names | Ceiriosen yr Aderyn | Prunus padus |
| All names | Celyn y Môr | Eryngium maritimum |
| All names | Celynnen | Ilex aquifolium |
| All names | Celynnen Ffrainc | Ruscus aculeatus |
| All names | Celynnen Mair | Ruscus aculeatus |
| All names | Cemeiddwellt | Parapholis strigosa |
| All names | Cenhinen | Allium ampeloprasum |
| All names | Cenhinen Bedr | Narcissus pseudonarcissus |
| All names | Cenhinen Dinbych | Dactylorhiza sambucina |
| All names | Cenhinen Gyffredin | Allium ampeloprasum |
| All names | Cenhinen y Brain | Endymion nonscriptus |
| All names | Cenhinen y Gwinwydd | Narcissus pseudonarcissus |
| All names | Cennin | Allium ampeloprasum |
| All names | Cennin Pedr | Narcissus pseudonarcissus |
| All names | Cennin y Brain | Endymion nonscriptus |
| All names | Cennin y Gog | Endymion nonscriptus |
| All names | Cerddinen | Sorbus aucuparia |
| All names | Cerddinen Ddof | Sorbus domestica |
| All names | Cerddinen Wen | Sorbus aria |
| All names | Cerddinen Wyllt | Sorbus torminalis |
| All names | Ceri | Sorbus aucuparia |
| All names | Cerwr Taliesin | Sedum telephium |
| All names | Ceulion | Galium verum |
| All names | Cheirchwellt Gwyllt y Gwanwyn | Avena fatua |
| All names | Cheirchwellt Gwyllt y Hydref | Avena sterilis |
| All names | Cheirchwellt Tal | Arrhenatherum elatius |
| All names | Chwein-hesgen | Carex pulicaris |
| All names | Chweinllys | Senecio cineraria |
| All names | Chweinllys y Maes | Senecio integrifolius |
| All names | Chweinllys y Morfa | Senecio congestus |
| All names | Chwerw Blewog | Cardamine hirsuta |
| All names | Chwerw Mawr | Cardamine amara |
| All names | Chwerw'r Coed | Cardamine flexuosa |
| All names | Chwerwlys | Artemisia absinthium |
| All names | Chwerwlys | Teucrium scorodonia |
| All names | Chwerwlys Torddail | Teucrium botrys |
| All names | Chwerwlys y Dŵr | Teucrium chamaedrys |
| All names | Chwerwlys y Môr | Artemisia maritima |
| All names | Chwerwlys y Môr Ogwyddflodeuog | Artemisia maritima |
| All names | Chwerwlys y Mur | Teucrium chamaedrys |
| All names | Chwerwlys y Twyn | Teucrium scorodonia |
| All names | Chwerwlys y Tywyn | Teucrium chamaedrys |
| All names | Chwerwlys yr Eithin | Teucrium scorodonia |
| All names | Chwerwlys yr Eithin | Teucrium chamaedrys |
| All names | Chwerwyn | Artemisia absinthium |
| All names | Chwerwyn Gwyn | Chrysanthemum parthenium |
| All names | Chwerwyn y Twyn | Teucrium scorodonia |
| All names | Chwerwyn yr Ardd | Chrysanthemum parthenium |
| All names | Chwyn Hallt | Salicornia stricta |
| All names | Chwys Arthur | Filipendula ulmaria |
| All names | Chwys Mair | Ranunculus bulbosus |
| All names | Chwys yr Haul | Drosera rotundifolia |
| All names | Chwys yr Huan | Drosera rotundifolia |
| All names | Chwysigenddail Cyffredin | Utricularia vulgaris |
| All names | Chwysigenddail lleiaf | Utricularia minor |
| All names | Chwysigenwraidd canolig | Utricularia ochroleuca |
| All names | Chwysigenwraidd Cyffredin | Utricularia vulgaris |
| All names | Chwysigenwraidd lleiaf | Utricularia minor |
| All names | Chwysolgen | Rumex conglomeratus |
| All names | Chwyth yr �d | Anthoxanthum odoratum |
| All names | Chwyth yr �d | Anthoxanthum odoratum |
| All names | Cibellyn | Allium schoenoprasum |
| All names | Cibellys | Allium schoenoprasum |
| All names | Cibog | Setaria verticillata |
| All names | Cibogwellt gwyrddlas | Setaria viridis |
| All names | Cibogwellt rhydd | Echinochloa crus-galli |
| All names | Cibogwellt Troellog | Setaria verticillata |
| All names | Cibyddlys | Allium schoenoprasum |
| All names | Cibyllyn | Allium schoenoprasum |
| All names | Cienioglys Cernyw | Sibthorpia europaea |
| All names | Ciog | Arctium lappa |
| All names | Ciros | Rosa canina |
| All names | Ciros | Rosa canina |
| All names | Ciros Gwyn | Rosa arvensis |
| All names | Claearllys | Sedum acre |
| All names | Claer | Salvia verbenacea |
| All names | Claerlys | Samolus valerandi |
| All names | Claes Mair (De Cymru) | Salvia verbenacea |
| All names | Clafrllys | Jovibarba sobolifera |
| All names | Clafrllys Bychan | Scabiosa columbaria |
| All names | Clafrllys Gwreidd-don | Succisa pratensis |
| All names | Clafrllys Lleiaf | Scabiosa columbaria |
| All names | Clafrllys Mawr | Inula helenium |
| All names | Clais | Jovibarba sobolifera |
| All names | Clais y Moch | Salvia pratensis |
| All names | Clais yr Hydd | Mercurialis |
| All names | Clais yr Hydd | Mercurialis perennis |
| All names | Clais yr Hydd Blynyddol | Mercurialis annua |
| All names | Clatsh y Cŵn | Digitalis purpurea |
| All names | Claw | Dianthus |
| All names | Clawa(e)n | Dianthus |
| All names | Cleci Coch | Digitalis purpurea |
| All names | Cleddlys | Sparganium erectum |
| All names | Cleddlys Bach | Sparganium minimum |
| All names | Cleddlys Culddail | Sparganium angustifolium |
| All names | Cleddlys Di-gainc | Sparganium simplex |
| All names | Cleddyflys | Sparganium erectum |
| All names | Cleddyflys Canghennog | Sparganium erectum |
| All names | Cleddyflys lleiaf | Sparganium minimum |
| All names | Cleddyflys Undwf Nofiadwy | Sparganium angustifolium |
| All names | Cleddyflys Undwf Syth | Sparganium simplex |
| All names | Clefryn | Jasione montana |
| All names | Cleyeyn | Dianthus |
| All names | Cleyrllys | Samolus valerandi |
| All names | Cloch Baban | Galanthus nivalis |
| All names | Cloch yr Eos | Campanula rotundifolia |
| All names | Clofer Goch | Trifolium pratense |
| All names | Clofer Hopys | Trifolium campestre |
| All names | Cloffrwym y Cythraul | Calystegia sepium |
| All names | Cloffrwym y Mwci | Calystegia sepium |
| All names | Clor | Conopodium majus |
| All names | Clôr y Brain | Saxifraga granulata |
| All names | Clows | Dianthus grantianopolitanus |
| All names | Clust Llygoden | Cerastium tetrandrum |
| All names | Clust llygoden coraidd a blodeuddail gwahanedig | Cerastium arvense |
| All names | Clust llygoden fach | Cerastium arvense |
| All names | Clust Llygoden Llydanddail | Cerastium glomeratum |
| All names | Clust Llygoden Mynyddig | Cerastium alpinum |
| All names | Clust Llygoden Pedwar-gwryw | Cerastium tetrandrum |
| All names | Clust y Fuwch | Verbascum thapsus |
| All names | Clust y Fuwch | Verbascum nigrum |
| All names | Clust y Gath | Hypochaeris radicata |
| All names | Clust y Lygoden | Hieracium pilosella |
| All names | Clust y Tarw | Verbascum nigrum |
| All names | Clust y Tarw | Verbascum thapsus |
| All names | Clust yr Arth | Sanicula europaea |
| All names | Clust yr Ewig | Daphne laureola |
| All names | Clustog Fair | Armeria maritima |
| All names | Clwm Eilun-Berllys | Torilis nodosa |
| All names | Clwpfrwynen arfor | Scirpus maritimus |
| All names | Clwpfrwynen Fach | Scirpus setaceus |
| All names | Clwpfrwynen Galafog | Eleocharis multicaulis |
| All names | Clwpfrwynen Gochddu | Eleocharis quinqueflora |
| All names | Clwpfrwynen Leiaf | Eleocharis acicularis |
| All names | Clwpfrwynen y Coed | Scirpus sylvaticus |
| All names | Clwpfrwynen y Gors | Eleocharis palustris |
| All names | Clwpfrwynen y morfa | Scirpus maritimus |
| All names | Clwpfrwynen yr Arfor | Scirpus maritimus |
| All names | Clych Duram | Salvia verbenacea |
| All names | Clych Enid | Convallaria majalis |
| All names | Clych y Meirch | Rhinanthus minor |
| All names | Clych y Perthi | Calystegia sepium |
| All names | Clychau Gleision | Endymion nonscriptus |
| All names | Clychau'r Eos | Endymion nonscriptus |
| All names | Clychau'r Gog | Endymion nonscriptus |
| All names | Clychau'r Grug | Erica cinerea |
| All names | Clychlys | Campanula |
| All names | Clychlys Amaryddail | Campanula rotundifolia |
| All names | Clychlys Bwytadwy | Campanula rapunculoides |
| All names | Clychlys Caer-gaint | Campanula medium |
| All names | Clychlys Clwstwr | Campanula glomerata |
| All names | Clychlys danadl | Campanula trachelium |
| All names | Clychlys Deilgrwn | Campanula rotundifolia |
| All names | Clychlys dynad-ddail | Campanula trachelium |
| All names | Clychlys Eiddew | Wahlenbergia hederacea |
| All names | Clychlys Eiddewddail | Wahlenbergia hederacea |
| All names | Clychlys Erfin | Campanula rapunculoides |
| All names | Clychlys Erfinwraidd | Campanula rapunculoides |
| All names | Clychlys lledaenol | Campanula patula |
| All names | Clychlys Llusg | Campanula rapunculoides |
| All names | Clychlys Mawr | Campanula latifolia |
| All names | Clychlys peatws-ddail | Campanula persicifolia |
| All names | Clychlys Sypddail | Campanula glomerata |
| All names | Clychlys y Cawr | Campanula latifolia |
| All names | Clychlys Ymlusgol | Campanula rapunculoides |
| All names | Clydogau | Melampyrum pratense |
| All names | Clymlys | Polygonum arenastrum |
| All names | Clymog | Polygonum arenastrum |
| All names | Cnau'r ddaear | Conopodium majus |
| All names | Cneuen y Ddaear Gyffedrin | Conopodium majus |
| All names | Cnwbfwsogl Carn Carw | Lycopodium clavatum |
| All names | Cnwbfwsolg Alpaidd | Lycopodium alpinum |
| All names | Cnwbfwsolg Mawr | Huperzia selago |
| All names | Cnwpfwsolg Bach | Selaginella selaginoides |
| All names | Cnwpfwsolg Syth Lleiaf | Selaginella selaginoides |
| All names | Cnwpfwsolg Syth Mwyaf | Huperzia selago |
| All names | Coch y llawr | Bartsia alpina |
| All names | Coch y llawr | Odontites verna |
| All names | Cochlas | Salvia verbenacea |
| All names | Cochwraidd | Rubia peregrina |
| All names | Cochyn Bratiog | Lychnis flos-cuculi |
| All names | Coden Fwg | Fumaria officinalis |
| All names | Codog | Onobrychis viciifolia |
| All names | Codowydd | Inula conyza |
| All names | Codrwth | Silene vulgaris |
| All names | Codwarth | Atropa belladonna |
| All names | Codwarth Caled | Solanum dulcamara |
| All names | Codwarth Du | Solanum nigrum |
| All names | Codywasg | Thlaspi arvense |
| All names | Codywasg y Maes | Thlaspi arvense |
| All names | Codywasg y Maes | Lepidium campestre |
| All names | Coed Bocs | Buxus sempervirens |
| All names | Coeden Afalau Surion | Malus sylvestris |
| All names | Coeden Bys y Blaidd | Lupinus arboreus |
| All names | Coeden Cnau Ffrengig | Juglans regia |
| All names | Coeden Drops | Fuchsia magellanica |
| All names | Coeden Gyrains | Ribes nigrum |
| All names | Coedfrwynen Flewog | Luzula sylvatica |
| All names | Coedfrwynen y Maes | Luzula campestris |
| All names | Coedglwm | Tamus communis |
| All names | Coedrwym | Tamus communis |
| All names | Coedwyrdd | Pyrola |
| All names | Coedwyrdd | Pyrola minor |
| All names | Coedwyrdd Bychan | Pyrola minor |
| All names | Coedwyrdd Bylchog | Orthilia secunda |
| All names | Coedwyrdd Crynddail | Pyrola rotundifolia |
| All names | Coedwyrdd Cyfryngol | Pyrola media |
| All names | Coedwyrdd Lleiaf | Pyrola minor |
| All names | Coedwyrdd Unblodeuyn | Moneses uniflora |
| All names | Coegberllys | Aethusa cynapium |
| All names | Collen | Corylus avellana |
| All names | Collen Ffrengig | Juglans regia |
| All names | Collwyn | Corylus avellana |
| All names | Coluddlys | Mentha pulegium |
| All names | Colwmbein | Aquilegia vulgaris |
| All names | Colyddlys | Mentha pulegium |
| All names | Cor-rosyn Gwyn y Mynydd | Helianthemum apenninum |
| All names | Cor-rosyn Lledlwyd | Helianthemum canum |
| All names | Corbysen | Vicia |
| All names | Corbysen Flewog | Vicia hirsuta |
| All names | Corbysen Lefn Bedwar-ronynnog | Vicia tetrasperma |
| All names | Cordegeirian | Orchis ustulata |
| All names | Corfrwynen | Rubus saxatilis |
| All names | Corglymig | Corrigiola litoralis |
| All names | Corhelygen | Salix repens |
| All names | Coriander | Coriandrum sativum |
| All names | Corn Carw | Crithmum maritimum |
| All names | Corn Carw'r Môr | Crithmum maritimum |
| All names | Corn Carw'r Mynydd | Lycopodium clavatum |
| All names | Corn Glas | Ajuga reptans |
| All names | Corn y Bwch | Orobanche rapum-genistae |
| All names | Corn y Carw | Plantago coronopus |
| All names | Corn yr Afr | Orobanche rapum-genistae |
| All names | Corn yr Hydd | Orobanche rapum-genistae |
| All names | Corn yr Iwrch | Orobanche rapum-genistae |
| All names | Cornfanadl | Genista tinctoria |
| All names | Cornwelltyn Camaidd | Parapholis strigosa |
| All names | Cornwelltyn y Morfa | Parapholis strigosa |
| All names | Cornwlyddyn | Cerastium tetrandrum |
| All names | Cornwlyddyn | Zannichellia palustris |
| All names | Cornwlyddyn coraidd a blodeuddail gwahanedig | Cerastium arvense |
| All names | Cornwlyddyn Llydanddail | Cerastium glomeratum |
| All names | Cornwlyddyn Pedwargwryw | Cerastium tetrandrum |
| All names | Cornwlyddyn Syth | Moenchia erecta |
| All names | Coronllys | Paeonia mascula |
| All names | Corsen | Phragmites australis |
| All names | Corsen y Sychdir | Calamagrostis epigeios |
| All names | Corsfrwynen | Schoenus nigricans |
| All names | Corsfrwynen Ddu | Schoenus nigricans |
| All names | Corsfrwynen rudd | Blysmus rufus |
| All names | Corsfrwynen Wen | Rynchospora alba |
| All names | Corswellt Amryliw | Phalaris arundinacea |
| All names | Corswellt y Tywod | Ammophila arenaria x |
| All names | Corswelltyn Rhuddlas | Sesleria caerulea |
| All names | Corswigen | Viburnum opulus |
| All names | Corwlydd Clymog | Sagina nodosa |
| All names | Corwlyddyn | Sagina |
| All names | Corwlyddyn anaf-flodeuog | Sagina apetala |
| All names | Corwlyddyn arfor | Sagina maritima |
| All names | Corwlyddyn Gorweddol | Sagina procumbens |
| All names | Corwlyddyn Mynawydaidd | Sagina saginoides |
| All names | Corwreiddrudd | Sherardia arvensis |
| All names | Corwynwyn | Allium schoenoprasum |
| All names | Corwyros | Cornus suecica |
| All names | Corysgawen | Sambucus ebulus |
| All names | Costog y Domen | Polygonum persicaria |
| All names | Cowman Bach Melyn | Senecio jacobaea |
| All names | Crabotsen | Malus sylvestris |
| All names | Cracheithin | Genista anglica |
| All names | Craf | Allium sativum |
| All names | Craf Ewinog | Allium sativum |
| All names | Craf Gwyllt | Allium vineale |
| All names | Craf y Geifr | Allium ursinum |
| All names | Craf y Gerddi | Allium sativum |
| All names | Craf y Nadroedd | Allium scorodoprasum |
| All names | Crafanc Hirddail | Ranunculus fluitans |
| All names | Crafanc Orweddol | Ranunculus repens |
| All names | Crafanc y Dŵr | Ranunculus aquatilis |
| All names | Crafanc y Frân | Ranunculus repens |
| All names | Crafanc y Frân Boethus y Gweunydd | Ranunculus acris |
| All names | Crafanc y Frân Syth-boeth | Ranunculus acris |
| All names | Crafanc y Frân Syth-boeth y Gweunydd | Ranunculus acris |
| All names | Crafanc y Frân Ymlusgaidd | Ranunculus repens |
| All names | Crafanc y Gŵr Drwg | Elymus repens |
| All names | Crafanc yr Arth | Helleborus foetidus |
| All names | Crafanc yr Arth | Helleborus viridis |
| All names | Crafanc yr Arth Ddrewedig | Helleborus foetidus |
| All names | Crafanc yr Eryr | Ranunculus scleratus |
| All names | Crafanc yr ꤼ/TD> | Ranunculus arvensis |
| All names | Craith Unmos | Veronica chamaedrys |
| All names | Craith Unnos | Prunella vulgaris |
| All names | Cramennog | Centaurea |
| All names | Cramennog Fwyaf | Centaurea scabiosa |
| All names | Cramennog yr ꤼ/TD> | Centaurea cyanus |
| All names | Creigberllys | Sison amomum |
| All names | Creiglys | Empetrum nigrum |
| All names | Creithig | Myrrhis odorata |
| All names | Creithig | Scandix pecten-veneris |
| All names | Creulys Bendigaid | Hypericum androsaemum |
| All names | Creulys Gyffredin | Senecio vulgaris |
| All names | Creulys Iago | Senecio jacobaea |
| All names | Creulys Llwyd | Senecio erucifolius |
| All names | Creulys Ludiog | Senecio viscosus |
| All names | Creulys Rhydychen | Senecio squalidus |
| All names | Creulys y Coed | Senecio sylvaticus |
| All names | Criafallen | Sorbus aucuparia |
| All names | Criafallen Gyffredin | Sorbus aria |
| All names | Criafallen Wen | Sorbus aria |
| All names | Criafallen Wyllt | Sorbus torminalis |
| All names | Criafolen | Sorbus torminalis |
| All names | Criafolen | Sorbus aucuparia |
| All names | Criafolen Wen | Sorbus aria |
| All names | Crib y Pannwr | Dipsacus fullonum |
| All names | Cribau Mair | Silybum marianum |
| All names | Cribau St.Ffraid | Stachys officinalis |
| All names | Cribau'r Bleiddiau | Arctium lappa |
| All names | Cribell Coch | Pedicularis sylvatica |
| All names | Cribell Felen | Rhinanthus minor |
| All names | Cribwellt | Koeleria gracilis |
| All names | Crinllys | Viola odorata |
| All names | Croeslys | Cruciata laevipes |
| All names | Croeso Gwanwyn | Narcissus pseudonarcissus |
| All names | Croeso Haf | Endymion nonscriptus |
| All names | Crogedyf | Filipendula vulgaris |
| All names | Cron | Heracleum sphondylium |
| All names | Cron y Gweunydd | Hydrocotyle vulgaris |
| All names | Crondoddaid | Umbilicus rupestris |
| All names | Cronnell | Trollius europaeus |
| All names | Cruelys Mawr | Sambucus ebulus |
| All names | Crwynllys | Gentiana pneumonanthe |
| All names | Crwynllys Chwerw | Gentianella anglica |
| All names | Crwynllys chwerw | Gentianella amarella |
| All names | Crwynllys y Gwanwyn | Gentiana verna |
| All names | Crwynllys y Maes | Gentianella campestris agg. |
| All names | Crwynllys y Rhos | Gentiana pneumonanthe |
| All names | Crydaethnen | Populus tremula |
| All names | Crydnydd | Lonicera periclymenum |
| All names | Crydwellt | Briza media |
| All names | Crydwellt Bychan | Briza minor |
| All names | Crys y Brenin | Hyoscyamus niger |
| All names | Cudd y Coed | Clematis vitalba |
| All names | Cwcwll y Mynach | Aconitum napellus |
| All names | Cwd y Mwg | Fumaria officinalis |
| All names | Cwfl y Mynach | Aconitum napellus |
| All names | Cwlwm Caraid | Paris quadrifolia |
| All names | Cwlwm y Coed | Tamus communis |
| All names | Cwlwm y Cythraul | Convulvulus arvensis |
| All names | Cwlwm y Gwŷdd | Tamus communis |
| All names | Cwlwm yr Asgwrn | Mercurialis perennis |
| All names | Cwlyn y Mêl | Agrimonia eupatoria |
| All names | Cwmffri | Symphytum officinale |
| All names | Cwpanau'r Brenin | Caltha palustris |
| All names | Cwt Ysgyfarnog | Lagurus ovatus |
| All names | Cwyros | Cornus sanguinea |
| All names | Cwyrwialen | Cornus sanguinea |
| All names | Cychwlyn | Agrimonia eupatoria |
| All names | Cycyll-lys Lleiaf | Scutellaria minor |
| All names | Cycyll-lys Mwyaf | Scutellaria galericulata |
| All names | Cycyllog | Scutellaria galericulata |
| All names | Cycyllog Bach | Scutellaria minor |
| All names | Cycyllog Lleiaf | Scutellaria minor |
| All names | Cycyllog Mwyaf | Scutellaria galericulata |
| All names | Cydllin | Camelina sativa |
| All names | Cyfagwy | Sempervivum tectorum |
| All names | Cyfardwf | Symphytum officinale |
| All names | Cyfardwf Oddyfnog | Symphytum tuberosum |
| All names | Cyfnydd | Cuscuta europaea |
| All names | Cyfoglys | Asarum europaeum |
| All names | Cyfrdwy | Osmunda regalis |
| All names | Cylor | Conopodium majus |
| All names | Cymalau'r Diafol | Galeopsis tetrahit |
| All names | Cynffon Llygoden | Myosurus minimus |
| All names | Cynffon Tytw | Reseda luteola |
| All names | Cynffon y Capwellt | Valeriana officinalis |
| All names | Cynffon y Ceiliog | Valeriana officinalis |
| All names | Cynffon y Gath | Typha latifolia |
| All names | Cynffon y Gath | Phleum pratense |
| All names | Cynffon y Gath Culddail | Typha angustifolia |
| All names | Cynffon y Gath Leiaf | Typha angustifolia |
| All names | Cynffonwellt Du | Alopecurus myosuroides |
| All names | Cynffonwellt Elinog | Alopecurus geniculatus |
| All names | Cyngaf | Galium aparine |
| All names | Cyngaf Bychan | Arctium minus |
| All names | Cyngaf Mawr | Arctium lappa |
| All names | Cyngaf y Coed | Arctium nemorosum |
| All names | Cynghafan | Galium aparine |
| All names | Cynghafan Mwyaf | Asperugo procumbens |
| All names | Cynghafog Arfor | Calystegia soldanella |
| All names | Cynghafog Fechan | Convulvulus arvensis |
| All names | Cynhafog Fawr | Calystegia silvatica |
| All names | Cynhowlen | Acer campestre |
| All names | Cynhowlen | Tanacetum vulgare |
| All names | Cypreswydden Lawson | Chamaecyparis lawsoniana |
| All names | Cyriawol | Sorbus aucuparia |
| All names | Cyrnddail | Ceratophyllum demersum |
| All names | Cyrnogyn pigfain | Phyteuma spicatum |
| All names | Cyrs (lluosog) | Phragmites australis |
| All names | Cysgadur | Solanum nigrum |
| All names | Cywarch | Cannabis sativa |
| All names | Cywarch Gwyllt | Eupatorium cannabinum |
| All names | Cywer y llaeth | Galium verum |
| All names | Daearllys | Paeonia mascula |
| All names | Dagrau Addaf | Staphylea pinnata |
| All names | Dagrau Mair | Primula veris |
| All names | Dail Bysedd Cochion | Digitalis purpurea |
| All names | Dail Ceiniog | Umbilicus rupestris |
| All names | Dail Clais | Taraxacum officinale |
| All names | Dail Crach | Digitalis purpurea |
| All names | Dail Cwlwm yr Asgwrn | Mercurialis perennis |
| All names | Dail Cwmffri | Symphytum officinale |
| All names | Dail Duon Bach | Scrophularia nodosa |
| All names | Dail Duon Da | Scrophularia nodosa |
| All names | Dail Ffion-ffrwyth | Digitalis purpurea |
| All names | Dail Llwynhidl | Plantago coronopus |
| All names | Dail Melfed | Verbascum thapsus |
| All names | Dail Robin | Glechoma hederacea |
| All names | Dail Robin | Geranium robertianum |
| All names | Dail Solomon | Polygonatum multiflorum |
| All names | Dail Tafol | Rumex obtusifolius |
| All names | Dail Troed yr Ebol | Tussilago farfara |
| All names | Dail y Beiblau | Hypericum androsaemum |
| All names | Dail y Dardog | Verbascum thapsus |
| All names | Dail y Fendigaid | Hypericum androsaemum |
| All names | Dail y Geiniog | Hydrocotyle vulgaris |
| All names | Dail y Groes | Polygonum persicaria |
| All names | Dail y Gron Lleiaf | Hydrocotyle vulgaris |
| All names | Dail y Peils | Ranunculus ficaria |
| All names | Dail y Tryfan | Petasites hybridus |
| All names | Dail y Twrch | Hypericum androsaemum |
| All names | Dail yr Hocys | Althaea officinalis |
| All names | Dail Ysgyrfi | Cochlearia officinalis |
| All names | Dalen Dda | Euphorbia |
| All names | Dalen Meiwyn | Datura stramonium |
| All names | Danadl Poethion | Urtica dioica |
| All names | Danadl Ysgar | Urtica dioica |
| All names | Danhadlen | Urtica dioica |
| All names | Danhadlen | Urtica |
| All names | Danhadlen Leiaf | Urtica urens |
| All names | Danhogen | Stachys officinalis |
| All names | Danhogen y Dŵr | Prunella vulgaris |
| All names | Danhogen y Dŵr | Scrophularia aquatica |
| All names | Dant y Ci | Taraxacum officinale |
| All names | Dant y Ci | Dactylis glomerata |
| All names | Dant y Llew Cyffredin | Taraxacum officinale |
| All names | Dant y Pysgodyn | Serratula tinctoria |
| All names | Dant y Pysgodyn Mynyddig | Saussurea alpina |
| All names | Dat | Asarum europaeum |
| All names | Deilen Ddu Dda | Scrophularia nodosa |
| All names | Deilen Gron | Umbilicus rupestris |
| All names | Deintlys | Cardamine bulbifera |
| All names | Deintlys Cennog | Lathraea squamaria |
| All names | Derig | Dryas octopetala |
| All names | Derlwys | Teucrium chamaedrys |
| All names | Derlys | Teucrium chamaedrys |
| All names | Derlys y Dŵr | Teucrium chamaedrys |
| All names | Derlys y Goedwig | Teucrium scorodonia |
| All names | Derwen Anwyw | Quercus ilex |
| All names | Derwen Bytholwyrdd | Quercus ilex |
| All names | Derwen Ddaildigoes | Quercus petraea |
| All names | Derwen Ddigoesog | Quercus petraea |
| All names | Derwen Goesog | Quercus robur |
| All names | Derwen y Ddaear | Teucrium chamaedrys |
| All names | Derwlys y Dŵr | Teucrium chamaedrys |
| All names | Di-sawr | Hesperis matronalis |
| All names | Diaddurn | Adoxa moschatellina |
| All names | Diadwyth | Valerianella locusta agg. |
| All names | Dibedolaid y Meirch | Botrychium lunaria |
| All names | Dibynlor | Conium maculatum |
| All names | Dibynlor | Tanacetum vulgare |
| All names | Dibynlor Cegidaidd | Oenanthe crocata |
| All names | Dibynlor Perllysddail | Oenanthe lachenalii |
| All names | Dibynlor Pibellaidd | Oenanthe fistulosa |
| All names | Didol | Cyclamen hederifolium |
| All names | Diflas | Atriplex |
| All names | Digoll Lwyd | Filago minima |
| All names | Dilosg | Sempervivum tectorum |
| All names | Dilwydd | Chelidonium majus |
| All names | Dilwydd Felen | Chelidonium majus |
| All names | Dindoll | Mespilus germanica |
| All names | Dinodd Barhaol | Scleranthus perennis |
| All names | Dinodd Flynyddol | Scleranthus annuus |
| All names | Dinodd Leiaf Benddu | Scleranthus annuus |
| All names | Diosglys Merllyn | Isoetes echinospora |
| All names | Distrewllys | Achillea ptarmica |
| All names | Diwlith | Adiantum capillus-veneris |
| All names | Diwlydd | Adiantum capillus-veneris |
| All names | Draenen Ddu | Prunus spinosa |
| All names | Draenen Wen | Crataegus monogyna |
| All names | Draenen Wen | Crataegus laevigata |
| All names | Draenen y Bwch | Rhamnus catharticus |
| All names | Draenen Ysbyddaden | Crataegus laevigata |
| All names | Drain Ysbyddaid | Crataegus monogyna |
| All names | Drewg Hirben Llyfn | Papaver dubium |
| All names | Drewg Hirben-Gwrychog | Papaver argemone |
| All names | Drewsawr | Ballota nigra |
| All names | Drigol | Rumex acetosella |
| All names | Dringiedydd | Clematis vitalba |
| All names | Dringol | Rumex acetosella |
| All names | Drysîen | Rubus plicatus |
| All names | Drysîen Bêr | Rosa rubiginosa agg. |
| All names | Duegredyn Meddygol | Phyllitis scolopendrium |
| All names | Duegredynen | Asplenium trichomanes |
| All names | Duegredynen Arfor | Asplenium marinum |
| All names | Duegredynen Ddu | Asplenium adiantum-nigrum |
| All names | Duegredynen Gwallt y Forwyn | Asplenium trichomanes |
| All names | Duegredynen Muriau | Asplenium ruta-muraria |
| All names | Duglwyd | Ononis repens |
| All names | Dugoesog | Asplenium adiantum-nigrum |
| All names | Dulys | Smyrnium olusatrum |
| All names | Dulys | Ligusticum scoticum |
| All names | Dulys cyffredin | Smyrnium olusatrum |
| All names | Duwallt y Forwyn | Asplenium adiantum-nigrum |
| All names | Dŵr-lyriad | Alisma |
| All names | Dwyfog | Stachys officinalis |
| All names | Dwygeinioglys | Lysimachia nummularia |
| All names | Dyfr-foronen | Sium latifolium |
| All names | Dyfr-foronen Llydanddail | Sium latifolium |
| All names | Dyfr-lyriad | Alisma |
| All names | Dyfr-lyriad Bychan | Baldellia ranunculoides |
| All names | Dyfr-lyriad Mwyaf | Alisma plantago-aquatica |
| All names | Dyfr-lyriad Nofiadwy | Antennaria dioica |
| All names | Dyfrforonen Gulddail | Berula erecta |
| All names | Dyfrforonen Sypflodeuog | Peucedanum ostruthium |
| All names | Dyfrforonen Sypflodeuog | Apium nodiflorum |
| All names | Dyfrllys Amryddail | Potamogeton gramineus |
| All names | Dyfrllys Arfor | Potamogeton filiformis |
| All names | Dyfrllys Camleswellt | Potamogeton compressus |
| All names | Dyfrllys Crych | Potamogeton crispus |
| All names | Dyfrllys Danheddog | Potamogeton crispus |
| All names | Dyfrllys Danheddog | Potamogeton pectinatus |
| All names | Dyfrllys Disglair | Potamogeton lucens |
| All names | Dyfrllys Eiddil | Potamogeton berchtoldii |
| All names | Dyfrllys Gwastatgoes | Potamogeton friesii |
| All names | Dyfrllys Gwelltog | Potamogeton obtusifolius |
| All names | Dyfrllys Gwrychddail | Potamogeton pectinatus |
| All names | Dyfrllys Llydanddail | Potamogeton natans |
| All names | Dyfrllys Meinddail | Potamogeton acutifolius |
| All names | Dyfrllys Nofiadwy | Potamogeton natans |
| All names | Dyfrllys Tewdws | Groenlandia densa |
| All names | Dyfrllys Trydwll | Potamogeton perfoliatus |
| All names | Dyfrllys y Gors | Potamogeton polygonifolius |
| All names | Dyfrwlyddyn | Montia |
| All names | Dyfrwlyddyn y Ffynnon | Montia |
| All names | Dynad | Urtica |
| All names | Dynad Coch | Lamium purpureum |
| All names | Dynhadlen | Urtica |
| All names | Dystrewlys | Achillea ptarmica |
| All names | Ebolgarn | Tussilago farfara |
| All names | Ebolgarn y gerddi | Asarum europaeum |
| All names | Ebolgarn y Môr | Calystegia soldanella |
| All names | Edafeddog | Filago germanica |
| All names | Edafeddog Benddu | Gnaphalium uliginosum |
| All names | Edafeddog Dlysog | Anaphalis margaritacea |
| All names | Edafeddog Dlysog | Anaphalis margaritacea |
| All names | Edafeddog Fynyddig | Antennaria dioica |
| All names | Edafeddog goraid y mynydd | Gnaphalium supinum |
| All names | Edafeddog Leiaf | Filago minima |
| All names | Edafeddog Lwyd | Gnaphalium uliginosum |
| All names | Edafeddog Lwyd | Filago germanica |
| All names | Edafeddog Melynwyn | Gnaphalium luteoalbum |
| All names | Edafeddog Unionsyth y Goedwig | Gnaphalium sylvaticum |
| All names | Edafeddog y Goedwig | Gnaphalium sylvaticum |
| All names | Edafeddog y Gors | Gnaphalium uliginosum |
| All names | Edafeddog y Môr | Otanthus maritimus |
| All names | Edafeddog y Mynydd | Antennaria dioica |
| All names | Edafeddog Ysgaredig | Antennaria dioica |
| All names | Efa | Plantago coronopus |
| All names | Effros | Euphrasia stricta |
| All names | Efrau | Lolium temulentum |
| All names | Efryn | Lolium perenne |
| All names | Efryn Coliog | Lolium temulentum |
| All names | Efryn Parhaus | Lolium perenne |
| All names | Efwr | Heracleum sphondylium |
| All names | Efyrllys | Heracleum sphondylium |
| All names | Egel | Cyclamen hederifolium |
| All names | Egfaenwydd | Crataegus laevigata |
| All names | Eglyn | Chrysosplenium oppositifolium |
| All names | Eglyn | Chrysosplenium oppositifolium |
| All names | Eglyn Cyferbynddail | Chrysosplenium oppositifolium |
| All names | Eglyn Cyferbynddail | Chrysosplenium oppositifolium |
| All names | Eglyn Cylchddail | Chrysosplenium alternifolium |
| All names | Eglyn Cylchddail | Chrysosplenium alternifolium |
| All names | Egroeswydd | Rosa canina |
| All names | Egroewydd | Rosa canina |
| All names | Egyllt | Ranunculus acris |
| All names | Eiddew | Hedera helix |
| All names | Eiddew'r Ddaear | Glechoma hederacea |
| All names | Eiddiorwg | Hedera helix |
| All names | Eidral | Glechoma hederacea |
| All names | Eidran | Origanum vulgare |
| All names | Eigryn | Briza media |
| All names | Eilgorros | Loiseleuria procumbens |
| All names | Eilun | Torilis |
| All names | Eilunberllys | Torilis arvensis |
| All names | Eilunberllys | Torilis japonica |
| All names | Eilunberllys bychan | Caucalis platycarpos |
| All names | Eirin Bwlas | Prunus insititia |
| All names | Eirin Gwion (Ffrwyth) | Bryonia dioica |
| All names | Eirin Gwion (Ffrwyth) | Tamus communis |
| All names | Eirin Mair | Ribes uva-crispa |
| All names | Eirin y Perthi | Prunus spinosa |
| All names | Eirinberth | Prunus spinosa |
| All names | Eirinen | Prunus domestica |
| All names | Eiriol | Galanthus nivalis |
| All names | Eirlys | Galanthus nivalis |
| All names | Eirŷaidd | Leucojum vernum |
| All names | Eiryaidd | Leucojum aestivum |
| All names | Eithin Mân | Ulex minor |
| All names | Eithinen Bêr | Juniperus communis |
| All names | Eithinen Ffrengig | Ulex europaeus |
| All names | Eithinen Goraidd | Ulex minor |
| All names | Eithinen y Cwrw | Juniperus communis |
| All names | Eithinen yr Iâr | Genista anglica |
| All names | Elebwr | Helleborus foetidus |
| All names | Elestr y Maes | Convallaria majalis |
| All names | Elestren | Lilium |
| All names | Elinog | Solanum dulcamara |
| All names | Elinog Goch | Polygonum persicaria |
| All names | Elisandyr | Smyrnium olusatrum |
| All names | Ellast | Carlina vulgaris |
| All names | Ellast | Carlina vulgaris |
| All names | Ellast Cyffredin | Carlina vulgaris |
| All names | Ellast Cyffredin | Carlina vulgaris |
| All names | Engraff | Butomus umbellatus |
| All names | Engraff | Butomus umbellatus |
| All names | Erbin Bach | Calamintha nepeta |
| All names | Erbin Cyffredin | Calamintha sylvatica |
| All names | Erchwaint | Filipendula ulmaria |
| All names | Erfinen | Brassica rapa |
| All names | Erfinen y Coed | Tamus communis |
| All names | Erfinen yr ꤼ/TD> | Brassica napus var. oleifera |
| All names | Erllyriad | Plantago |
| All names | Erllysg | Vinca major |
| All names | Erllysg Lleiaf | Vinca minor |
| All names | Erwain Helygddail | Spiraea salicifolia |
| All names | Erwaint | Filipendula ulmaria |
| All names | Eryraidd | Pteridium aquilinum |
| All names | Esgarlys Bychan | Aristolochia clematitis |
| All names | Esgid Fair | Cypripedium calceolus |
| All names | Esgidiau'r Gog | Viola odorata |
| All names | Esgob Gwyn | Leucanthemum vulgare |
| All names | Esgollys Crwn | Aristolochia clematitis |
| All names | Esgorlys Bychan | Aristolochia clematitis |
| All names | Euad | Dianthus |
| All names | Eur | Laburnum vulgare |
| All names | Eurberth | Ribes uva-crispa |
| All names | Eurddanadlen | Lamiastrum galeobdolon |
| All names | Eurddraenen | Ribes uva-crispa |
| All names | Eurddraenen Ddu | Ribes nigrum |
| All names | Eurfanadl | Genista tinctoria |
| All names | Eurinllys | Hypericum |
| All names | Eurinllys Blewog | Hypericum hirsutum |
| All names | Eurinllys Blodeufawr | Hypericum calycinum |
| All names | Eurinllys Mân Syth | Hypericum pulchrum |
| All names | Eurinllys Mân Ymdaenol | Hypericum humifusum |
| All names | Eurinllys Mawr | Hypericum maculatum |
| All names | Eurinllys Mynyddig | Hypericum montanum |
| All names | Eurinllys pedrongl | Hypericum tetrapterum |
| All names | Eurinllys Trydwll | Hypericum perforatum |
| All names | Eurinllys y Gors | Hypericum elodes |
| All names | Eurllys | Halimione portulacoides |
| All names | Eurllys | Halimione portulacoides |
| All names | Eurlys | Atriplex |
| All names | Eurwellt | Anthoxanthum odoratum |
| All names | Eurwellt | Anthoxanthum odoratum |
| All names | Eurwernen | Tilia vulgaris |
| All names | Eurwialen | Solidago virgaurea |
| All names | Ewinedd y Gath | Lotus corniculatus |
| All names | Ewnofiau Gwyllt | Hippocrepis comosa |
| All names | Ewr | Heracleum sphondylium |
| All names | F'anwylyd | Geum urbanum |
| All names | Fenyw | Senecio vulgaris |
| All names | Ferfaen | Verbena officinalis |
| All names | Feronica | Veronica |
| All names | Feronica Cyffredin | Veronica officinalis |
| All names | Ffa Ieir | Lotus corniculatus |
| All names | Ffa'r Gors | Menyanthes trifoliata |
| All names | Ffa'r Gors Teirdalen | Menyanthes trifoliata |
| All names | Ffacbys | Vicia |
| All names | Ffâen | Vicia faba |
| All names | Ffaen Cors Edd?og | Nymphoides peltata |
| All names | Ffaen Taleisin | Sedum telephium |
| All names | Ffâen y Moch | Hyoscyamus niger |
| All names | Ffanigl | Foeniculum vulgare |
| All names | Ffedog y Forwyn | Cardamine pratensis |
| All names | Ffenigl | Foeniculum vulgare |
| All names | Ffenigl Cyffredin | Foeniculum vulgare |
| All names | Ffenigl Helen Lueddog | Meum athamanticum |
| All names | Ffenigl Trymsawr | Foeniculum vulgare |
| All names | Ffenigl y Cŵn | Tripluerospermum maritimum agg. |
| All names | Ffenigl y Môr | Crithmum maritimum |
| All names | Ffetur | Avena fatua |
| All names | Ffion y Ffridd | Digitalis purpurea |
| All names | Fflamgoed | Euphorbia |
| All names | Fflamgoed Eiddil Fleanfain | Euphorbia exigua |
| All names | Fflamgoed Fechan | Euphorbia peplus |
| All names | Fflamgoed Ganghenddail | Euphorbia esula |
| All names | Fflamgoed gaperol | Euphorbia lathyrus |
| All names | Fflamgoed Gwigoedd | Euphorbia amygdaloides |
| All names | Fflamgoed Gyprysol | Euphorbia cyparissias |
| All names | Fflamgoed Lydanddail | Euphorbia platyphyllos |
| All names | Fflamgoed Ruddlas | Euphorbia peplis |
| All names | Fflamgoed Wyddelig | Euphorbia hyberna |
| All names | Fflamgoed y Morgreigiau | Euphorbia portlandica |
| All names | Ffon y Bugail | Dipsacus pilosa |
| All names | Ffon y Plant | Typha angustifolia |
| All names | Ffon y Plant | Typha latifolia |
| All names | Ffromlys | Impatiens noli-tangere |
| All names | Ffromlys Chwarennog | Impatiens glandulifera |
| All names | Ffrwyth Beilîaid | Arctium lappa |
| All names | Ffugbysen Faethol | Vicia sativa |
| All names | Ffugbysen Faethol Gyffredin | Vicia angustifolia |
| All names | Ffugbysen Felen Arw-godog | Vicia lutea |
| All names | Ffugbysen Gulddail Ruddog | Vicia angustifolia |
| All names | Ffugbysen Ruddlas Arw-godog | Vicia bithynica |
| All names | Ffugbysen y Cloddiau | Vicia sepium |
| All names | Ffugbysen y Gwanwyn | Vicia lathyroides |
| All names | Ffugbysen y Wig | Vicia sylvatica |
| All names | Ffunell | Foeniculum vulgare |
| All names | Ffwsia | Fuchsia magellanica |
| All names | Ffynidwydden Arian | Abies alba |
| All names | Ffynidwydden Douglas | Pseudotsuga taxifolia |
| All names | Ffyniwydd | Pinus sylvestris |
| All names | Ffynwewyr Ellyllon | Typha latifolia |
| All names | Ffynwewyr Ellyllon | Typha angustifolia |
| All names | Ffynwewyr y Plant | Typha angustifolia |
| All names | Ffynwewyr y Plant | Typha latifolia |
| All names | Fioled | Viola |
| All names | Fioled Bêr | Viola odorata |
| All names | Fioled Dauwynebog | Viola tricolor |
| All names | Fioled Felen Aeaf | Cheiranthus cheiri |
| All names | Fioled Felyn | Viola lutea |
| All names | Fioled y Cŵn | Viola canina |
| All names | Fioled y Dŵr | Hottonia palustris |
| All names | Fioled y Gors | Viola palustris |
| All names | Fioled y Mynydd | Viola lutea |
| All names | Garlleg | Allium sativum |
| All names | Garlleg Fynyddig | Allium carinatum |
| All names | Garlleg Gwyllt | Allium vineale |
| All names | Garlleg Mawr Pengrwn | Allium ampeloprasum |
| All names | Garlleg Rhesog y Maes | Allium oleraceum |
| All names | Garlleg y Berth | Alliaria petiolata |
| All names | Garlleg y Geifr | Allium ursinum |
| All names | Garlleg-ferwr | Alliaria petiolata |
| All names | Garllegog | Alliaria petiolata |
| All names | Garllegog Arfor | Alliaria petiolata |
| All names | Gefell-lys Dwy-ddalennog | Liparis loeselii |
| All names | Gefell-lys y Gors | Malaxis paludosa |
| All names | Gelaets | Iris pseudacorus |
| All names | Gellesgen | Iris pseudacorus |
| All names | Gellesgen Bêr | Acorus calamus |
| All names | Gellesgen Beraroglaidd | Acorus calamus |
| All names | Gellesgen Gyffredin | Iris pseudacorus |
| All names | Gellygbren | Pyrus communis |
| All names | Gellygen | Pyrus communis |
| All names | Gelyst | Iris pseudacorus |
| All names | Geuberllys | Aethusa cynapium |
| All names | Gewynllys | Ruscus aculeatus |
| All names | Gieulys | Ruscus aculeatus |
| All names | Gith | Agrostemma githago |
| All names | Githran | Sison amomum |
| All names | Githrog | Sison amomum |
| All names | Glas | Isatis tinctoria |
| All names | Glas y Gaeaf | Daphne laureola |
| All names | Glas y Gors | Myosotis palustris |
| All names | Glas y Graean | Echium vulgare |
| All names | Glas y Llwyn | Endymion nonscriptus |
| All names | Glasddu | Isatis tinctoria |
| All names | Glaslys | Isatis tinctoria |
| All names | Glasnoden y Môr | Zostera marina |
| All names | Glastonnen | Quercus ilex |
| All names | Glaswellt y Bwla | Molinia caerulea |
| All names | Glaswellt y Dŵr | Glyceria fluitans |
| All names | Glaswellt y Gweunydd | Molinia caerulea |
| All names | Glaswellt y Rhos | Danthonia decumbens |
| All names | Glesyn | Borago officinalis |
| All names | Glesyn Cyffredin | Borago officinalis |
| All names | Glesyn y Coed | Ajuga reptans |
| All names | Glesyn y Gaeaf | Pyrola minor |
| All names | Glesyn y Gaeaf | Pyrola |
| All names | Glesyn y Mynydd | Ajuga reptans |
| All names | Glesyn y Wiber | Echium vulgare |
| All names | Gliniogai | Melampyrum |
| All names | Gliniogai | Melampyrum pratense |
| All names | Gliniogai Cribog | Melampyrum cristatum |
| All names | Gliniogai Cyffredin | Melampyrum pratense |
| All names | Gliniogai Melyn | Melampyrum pratense |
| All names | Gliniogai'r Coed | Melampyrum sylvaticum |
| All names | Gloria | Iris |
| All names | Gloyglys | Euphrasia stricta |
| All names | Gloywlys | Euphrasia stricta |
| All names | Gludlys Arfor | Silene maritima |
| All names | Gludlys Coch | Silene dioica |
| All names | Gludlys Codrwth | Silene vulgaris |
| All names | Gludlys Cyffredin | Silene vulgaris |
| All names | Gludlys Cyffredin | Silene armeria |
| All names | Gludlys Gogwyddol | Silene nutans |
| All names | Gludlys Nos-flodeuol | Silene noctiflora |
| All names | Gludlys Rhesog | Silene conica |
| All names | Gludlys Ysbaenaidd | Silene otites |
| All names | Glyf | Malva |
| All names | Glyf Gyffredin | Malva sylvestris |
| All names | Glys | Sedum reflexum |
| All names | Godwllon | Hypericum maculatum |
| All names | Godwllon Mawr | Hypericum maculatum |
| All names | Godywydd | Nymphaea alba |
| All names | Golaeth | Lactuca sativa |
| All names | Golchenid | Ajuga reptans |
| All names | Golchenid Cyffredin | Ajuga reptans |
| All names | Golcheuraid | Sanicula europaea |
| All names | Golchwraidd | Sanicula europaea |
| All names | Golchyddes | Sanicula europaea |
| All names | Gold | Chrysanthemum segetum |
| All names | Gold Mair | Chrysanthemum segetum |
| All names | Gold y Gors | Caltha palustris |
| All names | Gold yr ꤼ/TD> | Chrysanthemum segetum |
| All names | Goleudrem | Euphrasia stricta |
| All names | Golwg Crist | Salvia verbenacea |
| All names | Golwg Crist | Euphrasia stricta |
| All names | Gorchwraidd | Salvia verbenacea |
| All names | Gorchwyraid | Salvia verbenacea |
| All names | Gorchwyrydd | Salvia verbenacea |
| All names | Goreunerth | Scrophularia nodosa |
| All names | Gorfanadl | Orobanche rapum-genistae |
| All names | Gorfanc Coch | Orobanche alba |
| All names | Gorfanc eiddew | Orobanche hederae |
| All names | Gorfanc ganghennog | Orobanche ramosa |
| All names | Gorfanc glasgoch | Orobanche purpurea |
| All names | Gorfanc hir | Orobanche gracilis |
| All names | Gorfanc lleiaf | Orobanche minor |
| All names | Gorfanc Mwyaf | Orobanche rapum-genistae |
| All names | Gorferini | Veronica beccabunga |
| All names | Gorhadog | Radiola linoides |
| All names | Gorhilig | Polycarpon tetraphyllum |
| All names | Gornerth | Scrophularia nodosa |
| All names | Gornerth Felen | Scrophularia scorodonia |
| All names | Gornerth y Dŵr | Scrophularia aquatica |
| All names | Gorthyfail | Anthriscus sylvestris |
| All names | Gorthyfail | Anthriscus sylvestris |
| All names | Gorthyfail Cyffredin | Anthriscus caucalis |
| All names | Gorthyfail Garw | Chaerophyllum temulentum |
| All names | Gorthyfail Llyfn | Anthriscus sylvestris |
| All names | Gorthyfail llyfn | Anthriscus sylvestris |
| All names | Gorthyfail y Gerddi | Anthriscus cerefolium |
| All names | Gorudd | Odontites verna |
| All names | Graban Deir-rhan | Bidens tripartita |
| All names | Graban Ogwydd | Bidens cernua |
| All names | Graban yr ꤼ/TD> | Chrysanthemum segetum |
| All names | Graeanllys y Dŵr | Veronica anagallis-aquatica |
| All names | Grawn y Llew | Buglossoides arvense |
| All names | Grawn y Perthi | Tamus communis |
| All names | Grawn y Perthi | Bryonia dioica |
| All names | Grawn yr Haul | Lithospermum officinale |
| All names | Greol | Bryonia dioica |
| All names | Greulys | Senecio sylvaticus |
| All names | Grêulys | Senecio vulgaris |
| All names | Greulys | Senecio jacobaea |
| All names | Greulys Fynyddol | Senecio sylvaticus |
| All names | Greulys Lledlwyd | Senecio erucifolius |
| All names | Greulys Lledlwyd Culddail | Senecio erucifolius |
| All names | Greulys y Gors | Senecio aquaticus |
| All names | Greuolen | Bryonia dioica |
| All names | Gromwel | Lithospermum officinale |
| All names | Grug | Erica cinerea |
| All names | Grug Croesddeiliog | Erica tetralix |
| All names | Grug Cyffredin | Calluna vulgaris |
| All names | Grug Cyffredin | Calluna vulgaris |
| All names | Grug Deilgroes | Erica tetralix |
| All names | Grug lledlwyd | Erica cinerea |
| All names | Grug y Mêl | Calluna vulgaris |
| All names | Grug Ysgub | Calluna vulgaris |
| All names | Grugbren | Tamarix gallica |
| All names | Grugeilyn Llyfn | Frankenia laevis |
| All names | Gruglys | Empetrum nigrum |
| All names | Grugwellt | Dactylis glomerata |
| All names | Gruw | Thymus |
| All names | Gruwlys | Thymus |
| All names | Gruwlys Gwyllt | Thymus serpyllum |
| All names | Gruwlys Gwyllt Mwyaf | Thymus pulegioides |
| All names | Grwmsyl | Senecio vulgaris |
| All names | Grwyswydd | Ribes uva-crispa |
| All names | Grwyswydden | Ribes uva-crispa |
| All names | Grygon | Empetrum nigrum |
| All names | Gryw Gwyllt | Thymus serpyllum |
| All names | Gueberllys | Aethusa cynapium |
| All names | Guelin y Forwyn | Thesium humifusum |
| All names | Gueperwraidd | Astragalus glycyphyllos |
| All names | Gwaed y Gwŷr | Hypericum androsaemum |
| All names | Gwaed y Gwŷr | Sambucus ebulus |
| All names | Gwaedlys | Lythrum salicaria |
| All names | Gwaedlys | Polygonum arenastrum |
| All names | Gwaedlys bychan | Odontites verna |
| All names | Gwaedlys Gwyn | Verbena officinalis |
| All names | Gwaedlys Mawr | Lythrum salicaria |
| All names | Gwaglwyfen | Tilia vulgaris |
| All names | Gwair Merllyn | Isoetes echinospora |
| All names | Gwalchlys Drewllyd | Crepis foetida |
| All names | Gwalchlys Garwaidd | Crepis biennis |
| All names | Gwalchlys y Gors | Crepis paludosa |
| All names | Gwalchlysiau | Crepis |
| All names | Gwallt Gwener | Adiantum capillus-veneris |
| All names | Gwanwden | Vinca major |
| All names | Gwanwden Lleiaf | Vinca minor |
| All names | Gwayw'r Brain | Narthecium ossifragum |
| All names | Gwayw'r Brenin | Narthecium ossifragum |
| All names | Gwden y Coed | Calystegia sepium |
| All names | Gwe Felen | Anthyllis vulneraria |
| All names | Gweddlys | Isatis tinctoria |
| All names | Gwell na'r Aur | Valeriana officinalis |
| All names | Gwellt y Gamlas | Zostera marina |
| All names | Gwellt y Gweunydd | Poa pratensis |
| All names | Gwelltfrwynen | Luzula campestris |
| All names | Gwendon | Galium palustre |
| All names | Gwendon arw y mign | Galium uliginosum |
| All names | Gwendon lefn | Galium saxatile |
| All names | Gwengraith | Sanicula europaea |
| All names | Gwenith y Brain | Sedum anglicum |
| All names | Gwenith y Ddaear | Ranunculus ficaria |
| All names | Gwenith y Gog | Scrophularia nodosa |
| All names | Gwenith y Gog | Ranunculus ficaria |
| All names | Gwenith yr Bwch | Fagopyrum sagittatum |
| All names | Gwenith yr Hydd | Fagopyrum sagittatum |
| All names | Gwenith Ysgyfarnog | Briza media |
| All names | Gwenithwellt | Elymus repens |
| All names | Gwenithwellt Brwynaidd | Elymus farctus |
| All names | Gwenithwellt Brwynaidd y Forlan | Elymus farctus |
| All names | Gwenithwellt Sypwraidd Coliog | Elymus caninus |
| All names | Gwenithwellt y Ci | Elymus caninus |
| All names | Gwenithwellt Ymdaenol | Elymus repens |
| All names | Gwenonwy | Convallaria majalis |
| All names | Gwenwialen | Tanacetum vulgare |
| All names | Gwenwialen | Acer campestre |
| All names | Gwenwlydd lefn | Galium saxatile |
| All names | Gwenwlydd y Gors | Galium palustre |
| All names | Gwenynddail | Melissa officinalis |
| All names | Gwenynllys cyffredin | Melissa officinalis |
| All names | Gwenynlys | Melissa officinalis |
| All names | Gwenynog | Melittis melissophylum |
| All names | Gwenynog lasgoch a gwyn | Melittis melissophylum |
| All names | Gwenynog wen-goch | Melittis melissophylum |
| All names | Gwerddig | Trientalis europaea |
| All names | Gwerddonell | Salvia verbenacea |
| All names | Gwerddonell y Waun | Salvia pratensis |
| All names | Gwernen | Alnus glutinosa |
| All names | Gwernen Lwyd | Alnus incana |
| All names | Gwerog | Plantago maritima |
| All names | Gweunblu | Eriophorum angustifolium |
| All names | Gweunwellt | Poa pratensis |
| All names | Gweunwellt Anhyblyg | Desmazeria rigida |
| All names | Gweunwellt Arfor | Puccinellia maritima |
| All names | Gweunwellt Blynyddol | Poa annua |
| All names | Gweunwellt Cyngwasgedig | Poa compressa |
| All names | Gweunwellt Cywasg | Poa compressa |
| All names | Gweunwellt Gorweiddiog | Danthonia decumbens |
| All names | Gweunwellt Lledarw | Poa trivialis |
| All names | Gweunwellt Llyfn | Poa pratensis |
| All names | Gweunwellt nof | Glyceria fluitans |
| All names | Gweunwellt Unflwydd | Poa annua |
| All names | Gweunwellt y Goedwig | Poa nemoralis |
| All names | Gwewydd | Ligustrum vulgare |
| All names | Gwewyrllys | Foeniculum vulgare |
| All names | Gwialen euraid | Solidago virgaurea |
| All names | Gwiberlys | Echium vulgare |
| All names | Gwiberlys Cyffredin | Echium vulgare |
| All names | Gwibredynen | Blechnum spicant |
| All names | Gwifwrnwydd | Viburnum lantana |
| All names | Gwifwrnwydd y Gors | Viburnum opulus |
| All names | Gwilffrai | Achillea millefolium |
| All names | Gwillion | Asparagus officinalis |
| All names | Gwinien | Vitis vinifera |
| All names | Gwiniolen | Tanacetum vulgare |
| All names | Gwiniolwydd | Tanacetum vulgare |
| All names | Gwinwydden | Vitis vinifera |
| All names | Gwiolydd | Viola |
| All names | Gwiolydd Cyffredin | Viola riviniana |
| All names | Gwiolydd Flewog | Viola hirta |
| All names | Gwiolydd y Goedwig | Viola reichenbachiana |
| All names | Gwiolydd y Gors | Viola palustris |
| All names | Gwir Garaid | Paris quadrifolia |
| All names | Gwiwydden | Populus tremula |
| All names | Gwlith yr Haul | Drosera rotundifolia |
| All names | Gwlithlys | Drosera rotundifolia |
| All names | Gwlithlys Hirddail | Drosera intermedia |
| All names | Gwlithlys Mawr | Drosera anglica |
| All names | Gwlydd | Stellaria media |
| All names | Gwlydd Gronynnog | Cucubalus baccifer |
| All names | Gwlydd llydanfrig | Holosteum umbellatum |
| All names | Gwlydd Mair | Anagallis arvensis |
| All names | Gwlydd Melyn Mair | Lysimachia nemorum |
| All names | Gwlydd y Cywion | Stellaria media |
| All names | Gwlydd y Geifr | Silene maritima |
| All names | Gwlydd y Gwyddau | Stellaria media |
| All names | Gwlydd yr Dom | Stellaria media |
| All names | Gwlydd yr Ieir | Stellaria media |
| All names | Gwlyddyn Garw | Galium aparine |
| All names | Gwlyddyn Mair Gwryw | Anagallis arvensis |
| All names | Gwlyddyn Mair y Gors | Anagallis tenella |
| All names | Gwlyddyn y Perthi | Galium aparine |
| All names | Gwniadur Mair | Digitalis purpurea |
| All names | Gwreidd-don | Succisa pratensis |
| All names | Gwreiddber | Astragalus glycyphyllos |
| All names | Gwreiddiriog | Pimpinella saxifraga |
| All names | Gwreiddiriog Cyffredin | Pimpinella saxifraga |
| All names | Gwreiddiriog cyffredin | Pimpinella saxifraga |
| All names | Gwreiddiriog Fawr | Pimpinella major |
| All names | Gwreiddiriog Mawr | Pimpinella major |
| All names | Gwreiddrudd | Rubia peregrina |
| All names | Gwreiddrudd Gwyllt | Rubia peregrina |
| All names | Gwrnerth | Veronica officinalis |
| All names | Gwroith | Tanacetum vulgare |
| All names | Gwrthbwys | Asarum europaeum |
| All names | Gwrthlys | Asarum europaeum |
| All names | Gwsberins | Ribes uva-crispa |
| All names | Gwsberis | Ribes uva-crispa |
| All names | Gwyarllys | Lythrum salicaria |
| All names | Gwyarllys Isop-ddail | Lythrum hyssopifolia |
| All names | Gwyarllys Pigog | Lythrum salicaria |
| All names | Gwybybyr Chweochrol | Elatine triandra |
| All names | Gwybybyr Wythochrog | Elatine hydropiper |
| All names | Gŵydd-droed | Chenopodium |
| All names | Gŵydd-droed Gwyn | Chenopodium album |
| All names | Gŵydd-droed Gwynaidd | Chenopodium album |
| All names | Gwyddfid | Lonicera periclymenum |
| All names | Gwyddfid Syth | Lonicera xylosteum |
| All names | Gwyddlwdn cyffredin | Sanguisorba minor |
| All names | Gwyddlwyn Cyffredin | Sanguisorba minor |
| All names | Gwyddwydd | Lonicera periclymenum |
| All names | Gwydro | Melilotus altissimus |
| All names | Gwyfon | Ribes uva-crispa |
| All names | Gwyfon Barfog | Ribes uva-crispa |
| All names | Gwyfonwydd | Ribes uva-crispa |
| All names | Gwyfynnog | Verbascum blattaria |
| All names | Gwyg | Vicia cracca |
| All names | Gwygbysen | Vicia cracca |
| All names | Gwygyrnddail Cyffredin | Ceratophyllum demersum |
| All names | Gwylaeth | Lactuca sativa |
| All names | Gwylaeth Bigog | Lactuca virosa |
| All names | Gwylaeth Chwerw | Picris echioides |
| All names | Gwylaeth Gryf-arogl | Lactuca virosa |
| All names | Gwylaeth Leiaf | Lactuca saligna |
| All names | Gwylaeth y Fagwyr | Mycelis muralis |
| All names | Gwylaeth y Moch | Arnoseris minima |
| All names | Gwylaeth yr Hebog | Picris hieracioides |
| All names | Gwylaeth yr Oen | Valerianella locusta agg. |
| All names | Gwylaeth yr Oen Deintiog | Valerianella dentata |
| All names | Gwylltgeirch | Avena fatua |
| All names | Gwylydd Llygod | Hieracium pilosella |
| All names | Gwylyddyn y Dŵr | Montia |
| All names | Gwylyddyn y Ffynnon | Montia |
| All names | Gwyn y Dillad | Conium maculatum |
| All names | Gwyn y Dillad | Sorbus aria |
| All names | Gwyn y Merched | Potentilla anserina |
| All names | Gwyn y Merched | Potentilla reptans |
| All names | Gwyntai | Anemone nemorosa |
| All names | Gwynwydd | Lonicera periclymenum |
| All names | Gwynwydden Ddu | Tamus communis |
| All names | Gwyran | Phalaris arundinacea |
| All names | Gwyrdd y Coed | Pyrola |
| All names | Gwyrdd y Gaeaf | Pyrola |
| All names | Gwyrddling | Myrica gale |
| All names | Gwysglys | Viscum album |
| All names | Gwysonllys | Viscum album |
| All names | Gwythdydd | Hottonia palustris |
| All names | Gwythdydd y Gors | Hottonia palustris |
| All names | Gyblys | Oenanthe crocata |
| All names | Gylfinog | Narcissus pseudonarcissus |
| All names | Gylfinog Cyffredin | Narcissus pseudonarcissus |
| All names | Gylfinog Ddau-Flodeuog | Narcissus biflorus x |
| All names | Gylfinog farddol | Narcissus poeticus |
| All names | Gylfinog Welw | Narcissus biflorus x |
| All names | Gysblys | Conium maculatum |
| All names | Gystlys | Tanacetum vulgare |
| All names | Gystlys Cyffredin | Tanacetum vulgare |
| All names | Gywydd-droed Arfor | Suaeda maritima |
| All names | Had y Llygaid | Salvia verbenacea |
| All names | Haidd | Hordeum polystichum |
| All names | Halogan | Apium graveolens |
| All names | Hanner pan | Verbascum lychnitis |
| All names | Heboglys | Hieracium |
| All names | Heboglys Brith | Hieracium maculatum |
| All names | Heboglys Culddail | Hieracium umbellatum |
| All names | Heboglys euraid | Hieracium aurianticum |
| All names | Heboglys Mynyddig | Hieracium alpinum |
| All names | Heboglys Torllwyd | Hieracium pilosella |
| All names | Heboglys Torllwyd | Hieracium pilosella |
| All names | Heboglys y Gors | Crepis paludosa |
| All names | Heddig | Raphanus sativus |
| All names | Heddig Gwyllt | Raphanus raphanistrum |
| All names | Hegydd Arfor | Cakile maritima |
| All names | Hegydd y Morlan | Cakile maritima |
| All names | Heiddwellt y Coed | Hordelymus europaeus |
| All names | Heiddwellt y gweunydd | Hordeum secalinum |
| All names | Heiddwellt y Maes | Hordeum secalinum |
| All names | Heiddwellt y Morfa | Hordeum marinum |
| All names | Heiddwellt y muriau | Hordeum murinum |
| All names | Helesg | Iris |
| All names | Helygen | Salix |
| All names | Helygen Beraroglaidd | Salix pentandra |
| All names | Helygen Drigwryw Hirddail | Salix triandra |
| All names | Helygen Frau | Salix fragilis |
| All names | Helygen Grych Grynddail | Salix aurita |
| All names | Helygen grynddail | Salix atrocinerea |
| All names | Helygen Grynddail Fwyaf | Salix caprea |
| All names | Helygen Grynglustiog | Salix aurita |
| All names | Helygen Gyffredin Afonol | Salix viminalis |
| All names | Helygen Leiaf | Salix herbacea |
| All names | Helygen Mair | Myrica gale |
| All names | Helygen olewydd-ddail | Salix atrocinerea |
| All names | Helygen Wen | Salix alba |
| All names | Helygen Wiail | Salix viminalis |
| All names | Helygen y Cŵn | Salix repens |
| All names | Helyglys | Epilobium |
| All names | Helyglys Culddail | Epilobium palustre |
| All names | Helyglys Culddail y Fawnog | Epilobium palustre |
| All names | Helyglys Gwlyddyn-ddail | Epilobium alsinifolium |
| All names | Helyglys Hardd | Epilobium angustifolium |
| All names | Helyglys Lledwyd Mânflodeuog | Epilobium parviflorum |
| All names | Helyglys Llydan Llyfnddail | Epilobium montanum |
| All names | Helyglys Llydanddail | Epilobium montanum |
| All names | Helyglys Llyfn Llydanddail | Epilobium montanum |
| All names | Helyglys Mynyddig | Epilobium anagallidifolium |
| All names | Helyglys Pannog | Epilobium hirsutum |
| All names | Helyglys Pedrongl | Epilobium tetragonum |
| All names | Helyglys Pêr | Epilobium hirsutum |
| All names | Helyglys Rhosynnaidd | Epilobium parviflorum |
| All names | Helys Can | Halimione portulacoides |
| All names | Helys Unflwydd | Suaeda maritima |
| All names | Helys Ysbigog | Salsola kali |
| All names | Henllydan | Aristolochia clematitis |
| All names | Henllydan | Plantago coronopus |
| All names | Henllydan y Ffordd | Plantago major |
| All names | Henwr | Artemisia campestris |
| All names | Heonllys | Viscum album |
| All names | Hesgen | Carex |
| All names | Hesgen | Carex |
| All names | Hesgen Anghyfagos | Carex remota |
| All names | Hesgen Anghysbell | Carex distans |
| All names | Hesgen Arfor | Carex arenaria |
| All names | Hesgen Bengron | Carex pilulifera |
| All names | Hesgen Benigen Ddail | Carex panicea |
| All names | Hesgen Benwen | Carex curta |
| All names | Hesgen Bigog Leiaf | Carex echinata |
| All names | Hesgen braff-dywysennog | Carex riparia |
| All names | Hesgen Chwysigennaidd Ber-dywysennog | Carex vesicaria |
| All names | Hesgen Chwysigennaidd Ylfinfain | Carex rostrata |
| All names | Hesgen Ddeulasnod | Carex binervis |
| All names | Hesgen Ddibynnaidd Fwyaf | Carex pendula |
| All names | Hesgen Ddibynnaidd y Goedwig | Carex sylvatica |
| All names | Hesgen Ddu | Carex atrata |
| All names | Hesgen Dywyll-felen | Carex hostiana |
| All names | Hesgen Dywysennog Fwyaf | Carex otrubae |
| All names | Hesgen Dywysennog Fwyay | Carex vulpina |
| All names | Hesgen Eiddil Dywysennog | Carex acuta |
| All names | Hesgen Eurwerdd | Carex limosa |
| All names | Hesgen Feindwf | Carex tomentosa |
| All names | Hesgen Felen | Carex flava |
| All names | Hesgen Felfedog | Typha angustifolia |
| All names | Hesgen Felfedog Fwyaf | Typha latifolia |
| All names | Hesgen Felfedog Goraidd | Typha angustifolia |
| All names | Hesgen Felfedog Leiaf | Typha angustifolia |
| All names | Hesgen Ganolig-dywysennog | Carex acutiformis |
| All names | Hesgen Gynnar | Carex caryophyllea |
| All names | Hesgen Hirgylchaidd | Carex ovalis |
| All names | Hesgen Hiriain | Carex hirta |
| All names | Hesgen Lygliw Benlydd | Carex disticha |
| All names | Hesgen Oeder | Carex serotina |
| All names | Hesgen Oleulas Sythddail | Carex elata |
| All names | Hesgen oleulas wyrgamddail | Carex flacia |
| All names | Hesgen Rafunog Fwyaf | Carex paniculata |
| All names | Hesgen Rafunog Leiaf | Carex diandra |
| All names | Hesgen Seraidd | Carex echinata |
| All names | Hesgen Welwas | Carex pallescens |
| All names | Hesgen y Tywod | Carex arenaria |
| All names | Hesgen Ysgar | Carex dioica |
| All names | Heuffras | Euphrasia stricta |
| All names | Hiawl | Bryonia dioica |
| All names | Hir ei Hoedl | Anaphalis margaritacea |
| All names | Hocys | Malva |
| All names | Hocys Bychan | Malva neglecta |
| All names | Hocys Crynddail | Malva neglecta |
| All names | Hocys y Morfa | Althaea officinalis |
| All names | Hocysen Gyffredin | Malva sylvestris |
| All names | Hocysen Wyllt | Malva moschata |
| All names | Hocysen y Gors | Althaea officinalis |
| All names | Hocysen y Môr | Lavatera arborea |
| All names | Hocysenfws | Malva moschata |
| All names | Hocyswydden | Lavatera arborea |
| All names | Holliach | Viscum album |
| All names | Hopys | Humulus lupulus |
| All names | Hopysen | Humulus lupulus |
| All names | Hosanau'r Gog | Orchis mascula |
| All names | Huddygl (llygair) | Raphanus sativus |
| All names | Hwl | Bryonia dioica |
| All names | Hwp yr Ychen | Ononis repens |
| All names | Hyddgwyr | Prunus avium |
| All names | Hydyf | Cardamine pratensis |
| All names | Hydyf blewog | Cardamine hirsuta |
| All names | Hydyf Chwerw | Cardamine flexuosa |
| All names | Hydyf Mawr | Cardamine amara |
| All names | Hydyf y Waun | Cardamine pratensis |
| All names | Hyllgryg | Iris |
| All names | Hysop | Hyssopus officinalis |
| All names | Ieudawdd | Veronica officinalis |
| All names | Ieutawdd | Veronica officinalis |
| All names | Iorwg | Hedera helix |
| All names | Iris Ddrewllyd | Iris |
| All names | Iris Felen | Iris pseudacorus |
| All names | Isob | Hyssopus officinalis |
| All names | Isop | Hyssopus officinalis |
| All names | Iwrwg | Hedera helix |
| All names | Laeth-ysgallen yr ꤼ/TD> | Sonchus arvensis |
| All names | Laethwyg Mynyddig Rhuddlas | Astragalus danicus |
| All names | Laethwyg Per | Astragalus glycyphyllos |
| All names | Laethysgallen Gyffredin | Sonchus oleraceus |
| All names | Lafant y Môr | Limonium vulgare |
| All names | Leilac | Syringa vulgaris |
| All names | Lelog | Syringa vulgaris |
| All names | Lili | Lilium |
| All names | Lili Bengam | Narcissus pseudonarcissus |
| All names | Lili Ddŵr Felen | Nuphar lutea |
| All names | Lili Ddŵr Wen | Nymphaea alba |
| All names | Lili Fach Wen | Galanthus nivalis |
| All names | Lili Felen y Ddŵr | Nuphar lutea |
| All names | Lili Mai | Convallaria majalis |
| All names | Lili'r Dyffryn | Convallaria majalis |
| All names | Lili'r Dyfroedd | Convallaria majalis |
| All names | Lili'r Maes | Convallaria majalis |
| All names | Ling | Calluna vulgaris |
| All names | Ling | Calluna vulgaris |
| All names | Linnaea | Linnaea borealis |
| All names | Lladdfrwyn | Juncus articulatus |
| All names | Llaeth y Cythraul | Euphorbia peplus |
| All names | Llaeth y Gaseg | Lonicera periclymenum |
| All names | Llaeth y Geifr | Lonicera periclymenum |
| All names | Llaeth Ysgyfarnog | Euphorbia helioscopia |
| All names | Llaeth-ysgallen | Sonchus arvensis |
| All names | Llaethlys | Polygala vulgaris |
| All names | Llaethlys | Euphorbia |
| All names | Llaethlys Portland | Euphorbia portlandica |
| All names | Llaethlys y Môr | Euphorbia paralias |
| All names | Llaethwyg | Astragalus glycyphyllos |
| All names | Llaethygen | Lactuca sativa |
| All names | Llaethysgallen Arw | Sonchus arvensis |
| All names | Llafn y Bladur | Narthecium ossifragum |
| All names | Llafnlys Bach | Ranunculus flammula |
| All names | Llafnlys Mawr | Ranunculus lingua |
| All names | Llafrwynen | Juncus articulatus |
| All names | Llaneswill | Bartsia alpina |
| All names | Llanwenlys | Borago officinalis |
| All names | Llarwydden Ewrop | Larix decidua |
| All names | Llarwydden Japan | Larix kaempferi |
| All names | Llau'r Offeiriad | Galium aparine |
| All names | Llawegor | Cirsium arvense |
| All names | Llawethan | Polemonium caeruleum |
| All names | Llawr-Sirianen | Prunus laurocerasus |
| All names | Llawredynen y Derw | Polypodium vulgare |
| All names | Llawredynen y Fagwyr | Polypodium vulgare |
| All names | Lleathlys y Coed | Euphorbia amygdaloides |
| All names | Lleidlys | Limosella aquatica |
| All names | Llemfrwynen | Cladium mariscus |
| All names | Llemyg | Limonium vulgare |
| All names | Ller | Bromus secalinus |
| All names | Llewpard Dag | Doronicum pardalianches |
| All names | Llewyg y Blaidd | Humulus lupulus |
| All names | Llewyg y Llyngyr | Helleborus foetidus |
| All names | Llewyg yr Iâr | Hyoscyamus niger |
| All names | Lleynlys Cyffredin | Cochlearia officinalis |
| All names | Lliflys Mynyddig | Saussurea alpina |
| All names | Llin | Linum usitatissimum |
| All names | Llin Ardir | Linum usitatissimum |
| All names | Llin Culddail | Linum bienne |
| All names | Llin Cyffredin | Linum usitatissimum |
| All names | Llin y Fagwyr | Cymbalaria muralis |
| All names | Llin y Forwyn | Linaria vulgaris |
| All names | Llin y Llyffant | Linaria vulgaris |
| All names | Llin y Mynydd | Linum catharticum |
| All names | Llin y Tylwyth Teg | Linum catharticum |
| All names | Llinad | Lemna minor |
| All names | Llinad Eiddew | Lemna trisulca |
| All names | Llinad Mawr | Spirodela polyrrhiza |
| All names | Llinad y Dŵr Crythog | Lemna gibba |
| All names | Llinad y Dŵr Eiddewddail | Lemna trisulca |
| All names | Llinad y Dŵr Lleiaf | Lemna minor |
| All names | Llinad y Dŵr Mwyaf | Spirodela polyrrhiza |
| All names | Llinclwm | Cuscuta |
| All names | Llinclwm Mwyaf | Cuscuta europaea |
| All names | Llindag | Cuscuta |
| All names | Llindag Lleiaf | Cuscuta epithymum |
| All names | Llindag Mwyaf | Cuscuta europaea |
| All names | Llindig | Cuscuta |
| All names | Llindro | Spergula arvensis |
| All names | Llindro | Cuscuta |
| All names | Llindro Mwyaf | Cuscuta europaea |
| All names | Llinesg y Dŵr | Callitriche |
| All names | Llinesg y Dŵr | Myosoton aquaticum |
| All names | Lliwiog Las | Isatis tinctoria |
| All names | Lliwlys | Isatis tinctoria |
| All names | Lloeredynen Gyffedrin | Botrychium lunaria |
| All names | Lloerlys | Botrychium lunaria |
| All names | Llosglys | Melampyrum pratense |
| All names | Llosglys | Daphne mezereon |
| All names | Llowrig | Vinca major |
| All names | Llowrig Lleiaf | Vinca minor |
| All names | Lluglys Blodeyn Rhudd | Silene dioica |
| All names | Lluglys Gludiog | Lychnis viscaria |
| All names | Lluglys Gwyn | Silene alba |
| All names | Lluglys Gwyn | Silene alba |
| All names | Lluglys Hwyrol | Silene alba |
| All names | Lluglys Mynyddig | Lychnis alpina |
| All names | Lluglys yr Ychen | Silene dioica |
| All names | Lluglys Ysgar | Silene dioica |
| All names | Llus | Vaccinium myrtillus |
| All names | Llus Coch | Vaccinium vitis-idaea |
| All names | Llus Du y Mynydd | Empetrum nigrum |
| All names | Llus Eira | Symphoricarpos rivularis |
| All names | Llus y Brain | Empetrum nigrum |
| All names | Llusen | Vaccinium myrtillus |
| All names | Lluswydden | Vaccinium myrtillus |
| All names | Lluswydden Fawr | Vaccinium uliginosum |
| All names | Llwfach Albanaidd | Ligusticum scoticum |
| All names | Llwgr y Tewlaeth | Verbascum thapsus |
| All names | Llwyd y Cŵn | Marrubium vulgare |
| All names | Llwyd y Din | Potentilla anserina |
| All names | Llwyd y Ffordd | Gnaphalium uliginosum |
| All names | Llwyd y Ffordd | Filago germanica |
| All names | Llwyd yr Eithin | Teucrium scorodonia |
| All names | Llwydlas | Glaucium flavum |
| All names | Llwydlas | Glaucium flavum |
| All names | Llwydlys | Artemisia vulgaris |
| All names | Llwydwen Fach | Potentilla anserina |
| All names | Llwyf Cyffredin | Ulmus procera |
| All names | Llwyfanen Gyffredin | Ulmus procera |
| All names | Llwyfanen Lydanddail | Ulmus glabra |
| All names | Llwyglys | Inula helenium |
| All names | Llwylys Cyffredin | Cochlearia officinalis |
| All names | Llwylys Denmarc | Cochlearia danica |
| All names | Llwylys Lloegr | Cochlearia anglica |
| All names | Llwylys Lloegr | Cochlearia anglica |
| All names | Llwylys Llychlyn | Cochlearia danica |
| All names | Llwyn bonheddig | Otanthus maritimus |
| All names | Llwyn Cotymog | Santolina chamaecyparis |
| All names | Llwyn Neidr | Plantago lanceolata |
| All names | Llwyn y Cythraul | Papaver rhoeas |
| All names | Llwyn y Neidr | Plantago |
| All names | Llwyn y Tewlaeth | Verbascum thapsus |
| All names | Llwyn y Tewlaeth | Digitalis purpurea |
| All names | Llwynau'r Fagwyr | Sedum reflexum |
| All names | Llwynhidydd | Potentilla reptans |
| All names | Llwynhidydd | Plantago |
| All names | Llwynhidydd (Cwm Penmachno) | Plantago lanceolata |
| All names | Llwynhidydd Arfor | Plantago maritima |
| All names | Llwynhidydd Blewog | Plantago media |
| All names | Llwynhidydd Corn y Carw | Plantago coronopus |
| All names | Llwynhidydd Mawr | Plantago major |
| All names | Llychlyn y dŵr | Veronica beccabunga |
| All names | Llydan y Ffordd | Plantago coronopus |
| All names | Llydan y Ffordd | Plantago major |
| All names | Llydanddail | Sedum telephium |
| All names | Llyfenwy | Saxifraga granulata |
| All names | Llyfenwy | Saxifraga |
| All names | Llyflys | Serratula tinctoria |
| All names | Llygad Crist | Euphrasia stricta |
| All names | Llygad Doli | Veronica chamaedrys |
| All names | Llygad Glas | Veronica chamaedrys |
| All names | Llygad Llo Mawr | Leucanthemum vulgare |
| All names | Llygad Siriol | Euphrasia stricta |
| All names | Llygad y Bwgan | Papaver rhoeas |
| All names | Llygad y Cythraul | Papaver rhoeas |
| All names | Llygad y Dydd | Bellis perennis |
| All names | Llygad y Dydd Mawr | Leucanthemum vulgare |
| All names | Llygad y Goediar Gwanwynol | Adonis annua |
| All names | Llygad yr Ych | Anthemis tinctoria |
| All names | Llygad Ysgyfarnog | Potentilla palustris |
| All names | Llygadlym | Chelidonium majus |
| All names | Llygadlys | Chelidonium majus |
| All names | Llygaid Crist | Salvia verbenacea |
| All names | Llygaid Ebrill | Ranunculus ficaria |
| All names | Llygaid y Diniwed | Ranunculus ficaria |
| All names | Llygwyn | Atriplex |
| All names | Llygwyn Arfor | Atriplex littoralis |
| All names | Llygwyn arianaidd | Atriplex sabulosa |
| All names | Llygwyn Culddail | Atriplex patula |
| All names | Llygwyn Llyswyddaid | Halimione portulacoides |
| All names | Llygwyn Llyswyddaidd | Halimione portulacoides |
| All names | Llygwyn Tryfal | Atriplex hastata |
| All names | Llygwyn tryferddail Syth | Atriplex patula |
| All names | Llygwyn tyrfal | Atriplex patula |
| All names | Llym y Llygad | Chelidonium majus |
| All names | Llymddreiniog | Schoenus nigricans |
| All names | Llymeidfwyd | Sonchus oleraceus |
| All names | Llymfrwynen | Juncus acutus |
| All names | Llyngwren | Prunus padus |
| All names | Llynorlys | Stellaria media |
| All names | Llynwlyddyn Corniog | Zannichellia palustris |
| All names | Llyrcadys | Mentha pulegium |
| All names | Llyren | Alisma |
| All names | Llyriad | Plantago |
| All names | Llyriad Corn y Carw | Plantago coronopus |
| All names | Llyriad Llwydion | Plantago media |
| All names | Llyriad Llwynhidydd | Plantago lanceolata |
| All names | Llyriad Mwyaf | Plantago major |
| All names | Llyriad y Defaid | Plantago maritima |
| All names | Llyriad y Dŵr | Alisma |
| All names | Llyriad y Llynnoedd | Alisma plantago-aquatica |
| All names | Llyriad y Môr | Plantago maritima |
| All names | Llyriaid Llymion | Alisma plantago-aquatica |
| All names | Llyrlys | Salicornia stricta |
| All names | Llys Bened | Geum urbanum |
| All names | Llys Dwyfog | Stachys officinalis |
| All names | Llys Efa | Plantago coronopus |
| All names | Llys F'anwylyd | Geum rivale |
| All names | Llys Mair | Ajuga reptans |
| All names | Llys Melyn | Genista tinctoria |
| All names | Llys Perfigedd | Hypericum androsaemum |
| All names | Llys y Bystwn | Erophila verna |
| All names | Llys y Cywer | Galium verum |
| All names | Llys y dyfrglwyf | Asparagus officinalis |
| All names | Llys y Famog | Leonurus cardiaca |
| All names | Llys y Fors | Herniaria glabra |
| All names | Llys y Gwaedlif | Achillea millefolium |
| All names | Llys y Gŵr Da | Chenopodium aristatum |
| All names | Llys y gwrda | Chenopodium bonus-henricus |
| All names | Llys y Gwrda | Chenopodium bonus-henricus |
| All names | Llys y Gwrid | Pentaglottis sempervirens |
| All names | Llys y Gwynt (Ffrainc) | Anemone nemorosa |
| All names | Llys y Gynddaredd | Gnaphalium uliginosum |
| All names | Llys y Gynddaredd | Filago germanica |
| All names | Llys y Lludw | Senecio cineraria |
| All names | Llys y Llwynog | Geranium robertianum |
| All names | Llys y Milwr | Lythrum salicaria |
| All names | Llys y Neidr | Polygonum bistorta |
| All names | Llys y Poer | Silene vulgaris |
| All names | Llys y Sipsiwn | Lycopus europaeus |
| All names | Llys y Wennol | Chelidonium majus |
| All names | Llys yr Angel peraroglaidd | Angelica archangelica |
| All names | Llys yr Angel y Goedwig | Angelica sylvestris |
| All names | Llys yr Hebog | Hieracium vulgatum |
| All names | Llys yr Hudolesau | Lycopus europaeus |
| All names | Llys Ysgyfarnog | Coeloglossum viride |
| All names | Llys yt Ychen | Silene dioica |
| All names | Llysarllys | Isatis tinctoria |
| All names | Llysau Duon Bach | Vaccinium myrtillus |
| All names | Llysgwyn Drewllyd | Chenopodium vulvaria |
| All names | Llysi au'r Ehedydd | Consolida regalis |
| All names | Llysiau Cadwgan | Valeriana officinalis |
| All names | Llysiau Coludd | Mentha pulegium |
| All names | Llysiau Crist | Polygala vulgaris |
| All names | Llysiau Cristoffis | Actaea spicata |
| All names | Llysiau F'anwylyd | Geum urbanum |
| All names | Llysiau Gwyddelig | Pastinaca sativa |
| All names | Llysiau Gwynion y Gerddi | Pastinaca sativa |
| All names | Llysiau Iago | Senecio jacobaea |
| All names | Llysiau Ieuan | Artemisia vulgaris |
| All names | Llysiau Ifan | Artemisia vulgaris |
| All names | Llysiau Ioan | Hypericum perforatum |
| All names | Llysiau Llwyd | Artemisia vulgaris |
| All names | Llysiau Llywelyn | Veronica chamaedrys |
| All names | Llysiau Llywelyn | Veronica |
| All names | Llysiau Martagon | Lilium martagon |
| All names | Llysiau Paul | Primula vulgaris |
| All names | Llysiau Pen Tai | Sempervivum tectorum |
| All names | Llysiau Pengelyd | Centaurea nigra |
| All names | Llysiau Pumbys | Potentilla reptans |
| All names | Llysiau Robert | Geranium pratense |
| All names | Llysiau Simwnt | Malva moschata |
| All names | Llysiau Solomon | Polygonatum multiflorum |
| All names | Llysiau St.Mair (Cwm Penmachno) | Epilobium angustifolium |
| All names | Llysiau Steffan | Circaea lutetiana |
| All names | Llysiau Steffan Mynyddig | Circaea alpina |
| All names | Llysiau Taliesin | Sedum telephium |
| All names | Llysiau Tormaen | Saxifraga |
| All names | Llysiau'r Ais | Plantago lanceolata |
| All names | Llysiau'r Angel | Angelica sylvestris |
| All names | Llysiau'r Archoll | Mentha pulegium |
| All names | Llysiau'r bara | Coriandrum sativum |
| All names | Llysiau'r Blaidd | Aconitum napellus |
| All names | Llysiau'r Bleurwg | Centaurium minus |
| All names | Llysiau'r Bronau | Ranunculus ficaria |
| All names | Llysiau'r Bystwn | Draba incana |
| All names | Llysiau'r Bystwn Cyffredin | Erophila verna |
| All names | Llysiau'r Bystwn Nyddgodog | Draba incana |
| All names | Llysiau'r Bystwn y Muriau | Draba muralis |
| All names | Llysiau'r Clefyd Melyn | Chelidonium majus |
| All names | Llysiau'r Cribau | Dipsacus fullonum |
| All names | Llysiau'r Cryman | Anagallis arvensis |
| All names | Llysiau'r Cwlwm | Symphytum tuberosum |
| All names | Llysiau'r Cwlwm | Symphytum officinale |
| All names | Llysiau'r Cŵn | Pedicularis sylvatica |
| All names | Llysiau'r Cwsg | Papaver somniferum |
| All names | Llysiau'r Cyfog | Asarum europaeum |
| All names | Llysiau'r Cyrff | Artemisia campestris |
| All names | Llysiau'r Cywer | Galium verum |
| All names | Llysiau'r Ddannodd | Peucedanum ostruthium |
| All names | Llysiau'r Ddidol | Cyclamen hederifolium |
| All names | Llysiau'r Din | Polygonum hydropiper |
| All names | Llysiau'r Dom | Stellaria media |
| All names | Llysiau'r Dom | Polygonum persicaria |
| All names | Llysiau'r Drindod Trilliw | Viola tricolor |
| All names | Llysiau'r Drinod | Viola tricolor |
| All names | Llysiau'r Droedwst | Aegopodium podagraria |
| All names | Llysiau'r Dryw | Agrimonia eupatoria |
| All names | Llysiau'r Eglwys | Pedicularis sylvatica |
| All names | Llysiau'r Eryr Pêr | Galium odoratum |
| All names | Llysiau'r Esgyrn | Glechoma hederacea |
| All names | Llysiau'r Ewinor | Erophila verna |
| All names | Llysiau'r Fam | Leonurus cardiaca |
| All names | Llysiau'r Famaeth | Euphorbia paralias |
| All names | Llysiau'r Forwyn | Filipendula ulmaria |
| All names | Llysiau'r Fuddai | Agrimonia eupatoria |
| All names | Llysiau'r Galon | Leonurus cardiaca |
| All names | Llysiau'r Geiniog | Hydrocotyle vulgaris |
| All names | Llysiau'r Gerwyn | Glechoma hederacea |
| All names | Llysiau'r Giau | Ruscus aculeatus |
| All names | Llysiau'r Gingroen | Senecio jacobaea |
| All names | Llysiau'r Groes | Cruciata laevipes |
| All names | Llysiau'r Gwaed | Mentha pulegium |
| All names | Llysiau'r Gwalch | Crepis |
| All names | Llysiau'r Gwayw | Sempervivum tectorum |
| All names | Llysiau'r gwenyn | Melissa officinalis |
| All names | Llysiau'r Gwewyr | Foeniculum vulgare |
| All names | Llysiau'r Gwynwydd | Lonicera periclymenum |
| All names | Llysiau'r Gymalwst | Aegopodium podagraria |
| All names | Llysiau'r Hebog | Hieracium |
| All names | Llysiau'r Hidl | Galium aparine |
| All names | Llysiau'r Hudol | Verbena officinalis |
| All names | Llysiau'r Hychgryg | Iris |
| All names | Llysiau'r Lawlwm | Symphytum officinale |
| All names | Llysiau'r Llaeth | Polygala vulgaris |
| All names | Llysiau'r Llaw | Cheiranthus cheiri |
| All names | Llysiau'r Lliw | Isatis tinctoria |
| All names | Llysiau'r Llwy | Cochlearia officinalis |
| All names | Llysiau'r Llwynog | Geranium robertianum |
| All names | Llysiau'r Llwynog | Geranium pratense |
| All names | Llysiau'r Llygaid | Euphrasia stricta |
| All names | Llysiau'r Meheryn | Trifolium |
| All names | Llysiau'r meudwy | Chenopodium bonus-henricus |
| All names | Llysiau'r Milwr Coch | Lythrum salicaria |
| All names | Llysiau'r Milwr Melyn | Lysimachia vulgaris |
| All names | Llysiau'r Moch | Solanum nigrum |
| All names | Llysiau'r Oen | Valerianella locusta agg. |
| All names | Llysiau'r Paladr | Parietaria judaica |
| All names | Llysiau'r Pannwr | Dipsacus fullonum |
| All names | Llysiau'r Pannwr | Galium mollugo |
| All names | Llysiau'r Panwyr | Galium verum |
| All names | Llysiau'r Parlys | Primula veris |
| All names | Llysiau'r Pwdin | Mentha pulegium |
| All names | Llysiau'r Swynwr | Circaea lutetiana |
| All names | Llysiau'r Tarw | Centaurea scabiosa |
| All names | Llysiau'r Tryfal | Capsella bursa-pastoris |
| All names | Llysiau'r Twrch | Bryonia dioica |
| All names | Llysiau'r Tywyrch | Bryonia dioica |
| All names | Llysiau'r Ysgyfaint | Angelica sylvestris |
| All names | Llysiau'r Ysgyfaint | Pulmonaria longifolia |
| All names | Llysiau'r Ysgyfaint Arfor | Mertensia maritima |
| All names | Llysyrawt | Sanguisorba officinalis |
| All names | Llysyrllys | Sanguisorba officinalis |
| All names | Lobelia | Lobelia dortmanna |
| All names | Lobelia'r Dŵr | Lobelia dortmanna |
| All names | Loer-redynen Gyfrdwy | Osmunda regalis |
| All names | Lwsern | Medicago sativa |
| All names | Lymwellt | Elymus arenarius |
| All names | Lysiau'r Llew | Chelidonium majus |
| All names | Lysiau'r Wennol | Chelidonium majus |
| All names | Mad-felen | Centaurea nigra |
| All names | Madfelen | Centaurea |
| All names | Madr | Rubia peregrina |
| All names | Madrwydd | Myrica gale |
| All names | Madwysg Cyffredin | Aquilegia vulgaris |
| All names | Madyr | Rubia peregrina |
| All names | Madywydd | Myrica gale |
| All names | Maenhad Meddygol | Lithospermum officinale |
| All names | Maenhad yr ?r | Buglossoides arvense |
| All names | Maeswellt | Holcus mollis |
| All names | Maeswellt | Agrostis capillaris |
| All names | Maeswellt Addfain | Agrostis capillaris |
| All names | Maeswellt Cyffredin | Agrostis capillaris |
| All names | Maeswellt Gwrychog | Agrostis curtisii |
| All names | Maeswellt Gwyn y Coed | Agrostis stolonifera |
| All names | Maeswellt Gwyn y Waun | Agrostis stolonifera |
| All names | Maeswellt Mawr | Agrostis gigantea |
| All names | Maeswellt Rhedegog | Holcus mollis |
| All names | Maeswellt Rhedegog | Agrostis stolonifera |
| All names | Maeswellt Sypwraidd | Holcus lanatus |
| All names | Maeswellt y cŵn | Agrostis canina |
| All names | Mafonen | Rubus idaeus |
| All names | Mafonllwyn | Rubus idaeus |
| All names | Magl Chwannen | Senecio cineraria |
| All names | Maglys | Medicago lupulina |
| All names | Maglys Gwineuddu | Medicago lupulina |
| All names | Maglys Rhuddlas | Medicago sativa |
| All names | Magwyr Wen | Nymphaea alba |
| All names | Main Suran | Rumex acetosa |
| All names | Maip Gwylltion | Sinapis arvensis |
| All names | Malus | Malva |
| All names | Malw yr Hel | Althaea officinalis |
| All names | Mamlys | Leonurus cardiaca |
| All names | Mamog Ddrewllyd | Chenopodium vulvaria |
| All names | Man y Don | Plantago maritima |
| All names | Mandon | Galium odoratum |
| All names | Mandon Las yr ꤼ/TD> | Sherardia arvensis |
| All names | Mantell Fair | Alchemilla vulgaris |
| All names | Mantell Fair Fynyddig | Alchemilla alpina |
| All names | Mantell Fair Gyffredin | Alchemilla vulgaris |
| All names | Mantell Fair y Mynydd | Alchemilla alpina |
| All names | Mantell y Côr | Alchemilla vulgaris |
| All names | Manyglog | Solanum dulcamara |
| All names | Mapgoll | Geum urbanum |
| All names | Mapgoll Benedigeidlyn cyffredin | Geum urbanum |
| All names | Mapgoll Benedigeidlys | Geum urbanum |
| All names | Mapgoll glan y dŵr | Geum rivale |
| All names | Marchalan | Inula helenium |
| All names | Marchfeilionen | Trifolium pratense |
| All names | Marchfiaren | Rosa canina |
| All names | Marchfiaren | Rosa canina |
| All names | Marchfint | Mentha longifolia |
| All names | Marchredynen | Dryopteris filix-mas |
| All names | Marchredynen Fenyw | Athyrium filix-femina |
| All names | Marchredynen Wrychog | Polystichium lobatum |
| All names | Marchredynen Wryw | Dryopteris filix-mas |
| All names | Marchredynen Wryw | Dryopteris filix-mas |
| All names | Marchredynen y Gors | Thelypteris palustris |
| All names | Marchrhedynen y Mynydd | Dryopteris oreopteris |
| All names | Marchwellt | Elymus repens |
| All names | Marchwellt Arfor | Elymus pycnanthus |
| All names | Marchwellt Tywyn | Elymus farctus |
| All names | Marchwellt y Coed | Elymus caninus |
| All names | Marchysgallen | Cirsium vulgare |
| All names | Marddanhadlen | Ballota nigra |
| All names | Marddanhadlen | Lamium hybridum |
| All names | Marddanhadlen Ber | Marrubium vulgare |
| All names | Marddanhadlen Ddu | Ballota nigra |
| All names | Marddanhadlen Felen | Genista tinctoria |
| All names | Marddanhadlen Fraith | Lamium maculatum |
| All names | Marddanhadlen Goch | Lamium hybridum |
| All names | Marddanhadlen Goch Gylch-ddail | Lamium amplexicaule |
| All names | Marddanhadlen Goch-frech | Lamium maculatum |
| All names | Marddanhadlen WEn | Lamium album |
| All names | Marddynad | Ballota nigra |
| All names | Marddynad Pêr | Marrubium vulgare |
| All names | Marddynadlen Felen | Lamiastrum galeobdolon |
| All names | Marddynhadlen Goch Gron | Lamium amplexicaule |
| All names | Marwddanhadlen | Ballota nigra |
| All names | Masarnen | Acer pseudoplatanus |
| All names | Masarnwydd | Acer pseudoplatanus |
| All names | Masarnwydd Lleiaf | Acer campestre |
| All names | Masarnwydd Mwyaf | Acer pseudoplatanus |
| All names | Masarnwydden Leiaf | Tanacetum vulgare |
| All names | Maswellt Cheirchaidd | Arrhenatherum elatius |
| All names | Mawnwellt | Calamagrostis epigeios |
| All names | Mawnwellt Blewog | Calamagrostis canescens |
| All names | Meddalai | Malva |
| All names | Meddalai Gyffredin | Malva sylvestris |
| All names | Meddalai y Morfa | Althaea officinalis |
| All names | Meddlys | Filipendula ulmaria |
| All names | Meddyg Mair | Inula conyza |
| All names | Meddyg y Bugail | Inula conyza |
| All names | Meddyges | Viola |
| All names | Meddyges Ddu | Scrophularia nodosa |
| All names | Meddyges Las | Prunella vulgaris |
| All names | Meddyges Lwyd | Stachys officinalis |
| All names | Meddyglyn | Daucus carota |
| All names | Meddygon Menyw | Artemisia absinthium |
| All names | Meddygyn | Viola |
| All names | Mefus Gwyllt | Fragaria vesca |
| All names | Mefusbren | Arbutus unedo |
| All names | Mefusen | Fragaria vesca |
| All names | Mefusen | Fragaria |
| All names | Mefusen Fawr | Fragaria moschata |
| All names | Mefusen y Goedwig | Fragaria vesca |
| All names | Mefuswydd (Gogledd Cymru) | Fragaria |
| All names | Meilionen | Trifolium |
| All names | Meilionen fefusaidd | Trifolium fragiferum |
| All names | Meilionen Goch | Trifolium pratense |
| All names | Meilionen Ysgarlad | Trifolium incarnatum |
| All names | Meillion | Trifolium |
| All names | Meillion Gwyn | Trifolium repens |
| All names | Meillionen | Trifolium |
| All names | Meillionen Felen | Anthyllis vulneraria |
| All names | Meillionen Felen Eiddil | Trifolium micranthum |
| All names | Meillionen Felen Fechan | Anthyllis vulneraria |
| All names | Meillionen Felen Fechan | Trifolium dubium |
| All names | Meillionen fygiedig | Trifolium suffocatum |
| All names | Meillionen Gedenog | Trifolium arvense |
| All names | Meillionen Gorniog | Medicago falcata |
| All names | Meillionen Hopysaidd | Trifolium campestre |
| All names | Meillionen Olwen | Trifolium repens |
| All names | Meillionen Rychiog | Trifolium striatum |
| All names | Meillionen Wen | Trifolium repens |
| All names | Meillionen Wen Ymgudd | Trifolium subterraneum |
| All names | Meillionen Wyrgam | Trifolium medium |
| All names | Meillionen y Ceirw | Melilotus altissimus |
| All names | Meipen | Brassica rapa |
| All names | Meipen Fair | Bryonia dioica |
| All names | Meipen Fair | Tamus communis |
| All names | Meipen Fendigaid | Bryonia dioica |
| All names | Meipen yr ꤼ/TD> | Brassica napus var. oleifera |
| All names | Meipwn Fair | Bryonia dioica |
| All names | Meirion | Cannabis sativa |
| All names | Meiwyn | Datura stramonium |
| All names | Mêl y Gweunydd | Pedicularis palustris |
| All names | Mêl-y-cwn | Pedicularis sylvatica |
| All names | Melengu | Reseda luteola |
| All names | Melfedog | Verbascum thapsus |
| All names | Melged | Festuca richardsonii |
| All names | Melged | Beta vulgaris var. maritima |
| All names | Melged arfor | Beta vulgaris var. maritima |
| All names | Melic-wellt Rhuddlas | Melica nutans |
| All names | Meligwellt | Melica uniflora |
| All names | Meligwellt Gogwydd | Melica nutans |
| All names | Meligwellt y Goedwig | Melica uniflora |
| All names | Melog | Lonicera periclymenum |
| All names | Melog y Borfa | Pedicularis sylvatica |
| All names | Melog y Waun | Pedicularis palustris |
| All names | Melsugn | Pedicularis sylvatica |
| All names | Melsugn y Borfa | Pedicularis sylvatica |
| All names | Melyn y Gaeaf | Cheiranthus cheiri |
| All names | Melyn y Gors | Caltha palustris |
| All names | Melyn y Gwanwyn | Ranunculus ficaria |
| All names | Melyn y Gwanwyn | Scrophularia nodosa |
| All names | Melyn y Twynau | Potentilla erecta |
| All names | Melyn yr Eithin | Potentilla erecta |
| All names | Melyn yr Hwyr | Oenothera biennis |
| All names | Melyneuraidd | Solidago virgaurea |
| All names | Melynllys | Chelidonium majus |
| All names | Melynnyd | Hypochaeris radicata |
| All names | Melynnyd Brych | Hypochaeris maculata |
| All names | Melynnyd Brychog | Hypochaeris maculata |
| All names | Melynnyd Esmwyth | Hypochaeris glabra |
| All names | Melynnyd Gorwreiddiog | Hypochaeris radicata |
| All names | Melynnyd Moel | Hypochaeris glabra |
| All names | Melynog y Waun | Genista tinctoria |
| All names | Melynwellt | Anthoxanthum odoratum |
| All names | Melynwellt | Anthoxanthum odoratum |
| All names | Melynwellt Pêr y Gwanwyn | Anthoxanthum odoratum |
| All names | Melynwellt Pêr y Gwanwyn | Anthoxanthum odoratum |
| All names | Melynwellt y Gwanwyn | Anthoxanthum odoratum |
| All names | Melynwellt y Gwanwyn | Anthoxanthum odoratum |
| All names | Melyswraidd | Astragalus glycyphyllos |
| All names | Menyg Ellyllon | Digitalis purpurea |
| All names | Menyg Mair | Digitalis purpurea |
| All names | Menyg y Gog | Silene vulgaris |
| All names | Menyg y Llwynog | Digitalis purpurea |
| All names | Menyg y Tylwyth Teg | Digitalis purpurea |
| All names | Merddraenen | Rosa canina |
| All names | Merllys | Asparagus officinalis |
| All names | Merllys cyffredin | Asparagus officinalis |
| All names | Mers | Apium graveolens |
| All names | Merydd | Ammophila arenaria x |
| All names | Merysbren | Mespilus germanica |
| All names | Meryswydden | Mespilus germanica |
| All names | Meryw | Juniperus communis |
| All names | Merywen | Juniperus communis |
| All names | Merywen Gyffredin | Juniperus communis |
| All names | Mesuriad | Origanum vulgare |
| All names | Mesuriad Cyffredin | Origanum vulgare |
| All names | Metolai | Malva |
| All names | Metolai Gyffredin | Malva sylvestris |
| All names | Miaren | Rubus plicatus |
| All names | Mieren | Rubus plicatus |
| All names | Mierllwyn | Rubus plicatus |
| All names | Mierynllwyn | Rubus plicatus |
| All names | Mil Melyn y Gwanwyn | Ranunculus ficaria |
| All names | Milddail | Achillea millefolium |
| All names | Miled | Milium effusum |
| All names | Miledwellt | Milium effusum |
| All names | Milfeillionen | Trifolium repens |
| All names | Milfyw | Ranunculus ficaria |
| All names | Milfyw | Luzula campestris |
| All names | Millyn | Viola odorata |
| All names | Millyn Glas | Viola odorata |
| All names | Millyn Gwyn | Viola odorata |
| All names | Millynen | Viola odorata |
| All names | Milwydd | Anthemis nobilis |
| All names | Milwydd | Anthemis cotula |
| All names | Mintys | Mentha |
| All names | Mintys Blewog | Mentha aquatica |
| All names | Mintys culddail | Mentha gentilis |
| All names | Mintys Deilgrwn | Mentha suaveolens |
| All names | Mintys lled-grynddail | Mentha suaveolens |
| All names | Mintys Sbigog | Mentha spicata |
| All names | Mintys Troellaidd | Mentha verticillata |
| All names | Mintys y Creigiau | Origanum vulgare |
| All names | Mintys y dŵr | Mentha aquatica |
| All names | Mintys y Gath | Nepeta cataria |
| All names | Mintys y Graig | Origanum vulgare |
| All names | Mintys y Maes | Mentha arvensis |
| All names | Mintys y March | Mentha longifolia |
| All names | Mintys y Twynau | Calamintha sylvatica |
| All names | Mintys yr Âr | Mentha arvensis |
| All names | Mintys yr Ardir | Mentha arvensis |
| All names | Mintys yr ꤼ/TD> | Mentha arvensis |
| All names | Moch-ysgallen yr âr | Sonchus arvensis |
| All names | Mochlys | Solanum nigrum |
| All names | Mochlys Cyffredin | Solanum nigrum |
| All names | Mochlys Duon | Circaea lutetiana |
| All names | Mochlys Grawnddu | Solanum nigrum |
| All names | Mochlys Swynyddlys | Circaea lutetiana |
| All names | Mochwraidd | Cyclamen hederifolium |
| All names | Mochysgallen | Sonchus oleraceus |
| All names | Montbretia | Crocosmia cocosmiflora x |
| All names | Môr-Edafeddog | Otanthus maritimus |
| All names | Môr-hesg | Ammophila arenaria x |
| All names | Môr-hocysen | Lavatera arborea |
| All names | Moresg | Ammophila arenaria x |
| All names | Môrfrwynen | Juncus maritimus |
| All names | Môrgelynnen | Eryngium maritimum |
| All names | Môrlwyau Brutanaidd | Cochlearia anglica |
| All names | Môrlwyau Brytanaidd | Cochlearia anglica |
| All names | Môrlwyau Cyffredin | Cochlearia officinalis |
| All names | Môrlwyau Danaidd | Cochlearia danica |
| All names | Môrlwyau Eiddewddail | Cochlearia danica |
| All names | Môrlwyau Meddygol | Cochlearia officinalis |
| All names | Moron Gwylltion | Daucus carota |
| All names | Moron Gwynion | Pastinaca sativa |
| All names | Moron y Meysydd | Daucus carota |
| All names | Moronen Goch | Daucus carota |
| All names | Moronen y Maes | Daucus carota |
| All names | Moronen y Meirch | Heracleum sphondylium |
| All names | Moronen y Moch | Pastinaca sativa |
| All names | Mur-rwyddlwyn | Veronica arvensis |
| All names | Murlwyn | Parietaria judaica |
| All names | Murlys | Parietaria judaica |
| All names | Murwyll | Cheiranthus cheiri |
| All names | Murwyll Tewbannog Arfor | Matthiola sinuata |
| All names | Mwcog | Rosa spinosissima |
| All names | Mwdr(llygr) | Artemisia campestris |
| All names | Mwg y Ddaear | Fumaria officinalis |
| All names | Mwg y ddaear afreolus | Fumaria capreolata |
| All names | Mwg y ddaear gafaelgar | Corydalis claviculata |
| All names | Mwg y ddaear mânflodeuog | Fumaria parviflora |
| All names | Mwg y Ddaear Meddygol | Fumaria officinalis |
| All names | Mwglys | Adoxa moschatellina |
| All names | Mwsg | Mimulus moschatus |
| All names | Mwsglys | Adoxa moschatellina |
| All names | Mwstard Cyffredin | Brassica nigra |
| All names | Mwstard Gwyn | Sinapis alba |
| All names | Mwstard y Tywod | Diplotaxis muralis |
| All names | Mwstardd | Brassica nigra |
| All names | Mwyar y Brain | Vaccinium myrtillus |
| All names | Mwyaren | Rubus plicatus |
| All names | Mwyaren Berwyn | Rubus chamaemorus |
| All names | Mwyaren Ddu | Rubus plicatus |
| All names | Mwyaren Doewan | Rubus chamaemorus |
| All names | Mwyaren Mair | Rubus rubus |
| All names | Myltys | Nuphar lutea |
| All names | Mynawyd y Bugail | Geranium pratense |
| All names | Mynawydlys dyfrdrig | Subularia aquatica |
| All names | Mynyglog | Solanum dulcamara |
| All names | Mŷr-rhafnwydd | Hippophae rhamnoides |
| All names | Myrdd-ddail | Myriophyllum |
| All names | Myrdd-ddail Troellog | Myriophyllum verticillatum |
| All names | Myrdd-ddail Tywysennaidd | Myriophyllum spicatum |
| All names | Myrddail | Myriophyllum |
| All names | Myrydd | Ammophila arenaria x |
| All names | Na'd Fi'n Angol | Myosotis arvensis |
| All names | Na'd Fi'n Angol | Myosotis palustris |
| All names | Neidrlys | Polygonum bistorta |
| All names | Nele | Hypericum |
| All names | Nodwydd y Bugail | Scandix pecten-veneris |
| All names | Nyth Aderyn | Daucus carota |
| All names | Oestrywydden | Carpinus betulus |
| All names | Ofergaru | Viola arvensis |
| All names | Ogfaenllwyn | Rosa canina |
| All names | Ogfaenllwyn | Rosa canina |
| All names | Olbrain | Coronopus squamatus |
| All names | Olbrain Dafadennog | Coronopus squamatus |
| All names | Olbrain Lleiaf | Coronopus didymus |
| All names | Olfran | Coronopus squamatus |
| All names | Onwydden | Fraxinus excelsior |
| All names | Orfanc | Orobanche rapum-genistae |
| All names | Orpin | Sedum telephium |
| All names | Pabi Bychan | Papaver argemone |
| All names | Pabi Coch | Papaver rhoeas |
| All names | Pabi Corniog Melyn | Glaucium flavum |
| All names | Pabi Corniog Melyn | Glaucium flavum |
| All names | Pabi Crynben Pigog | Papaver hybridum |
| All names | Pabi Crynben-Gwrychog | Papaver hybridum |
| All names | Pabi Cymreig | Meconopsis cambrica |
| All names | Pabi Cymru | Meconopsis cambrica |
| All names | Pabi Hirben Llyfn | Papaver dubium |
| All names | Pabi Hirben-Gwrychog | Papaver argemone |
| All names | Pabi Melyn | Meconopsis cambrica |
| All names | Pabi'r Gwenith | Agrostemma githago |
| All names | Pabicrynben Llyfn | Papaver rhoeas |
| All names | Pabwyren | Juncus effusus |
| All names | Paderau'r Gath | Tamus communis |
| All names | Paladr Blodeuwyrdd | Coeloglossum viride |
| All names | Paladr Hir | Orobanche rapum-genistae |
| All names | Paladr trwyddo | Bupleurum rotundifolium |
| All names | Paladr trwyddo eiddilddail | Bupleurum tenuissimum |
| All names | Paladr y Wal | Parietaria judaica |
| All names | Palf neu Droed y Llew | Alchemilla vulgaris |
| All names | Palf y Blaidd | Lycopodium clavatum |
| All names | Palf y Gath Bali | Ajuga chamaepitys |
| All names | Palf yr Arth | Helleborus foetidus |
| All names | Panasen | Pastinaca sativa |
| All names | Panasen y Cawr | Heracleum sphondylium |
| All names | Panasen y dŵr | Sium latifolium |
| All names | Pannas | Pastinaca sativa |
| All names | Pannog | Verbascum |
| All names | Pannog Brithgoch | Verbascum phoeniceum |
| All names | Pannog Melyn | Verbascum thapsus |
| All names | Pared y Mur | Parietaria judaica |
| All names | Paredlys | Parietaria judaica |
| All names | Parfyg | Hyoscyamus niger |
| All names | Pawen yr Arth | Helleborus foetidus |
| All names | Pawrwellt anhiliog | Bromus sterilis |
| All names | Pawrwellt hirfain | Festuca gigantea |
| All names | Pawrwellt Ller | Bromus secalinus |
| All names | Pawrwellt llyfn | Bromus racemosus |
| All names | Pawrwellt Maswy | Bromus hordeaceus |
| All names | Pawrwellt unionsyth | Bromus erectus |
| All names | Pawrwellt y Eiddil y Goedwig | Brachypodium sylvaticum |
| All names | Pawrwellt y Goedwig | Brachypodium sylvaticum |
| All names | Pedol y March | Hippocrepis comosa |
| All names | Pefrwellt | Phalaris canariensis |
| All names | Pefrwellt amaethol | Phalaris canariensis |
| All names | Peisgwellt | Festuca pratensis |
| All names | Peisgwellt | Festuca arundinacea |
| All names | Peisgwellt Anhiliog | Vulpia bromoides |
| All names | Peisgwellt Caledaidd | Festuca trachyphylla |
| All names | Peisgwellt Coch | Festuca rubra |
| All names | Peisgwellt hirian | Festuca arundinacea |
| All names | Peisgwellt hirion | Festuca gigantea |
| All names | Peisgwellt Hydwf | Festuca arundinacea |
| All names | Peisgwellt Mawr | Festuca gigantea |
| All names | Peisgwellt Uncib | Vulpia fasciculata |
| All names | Peisgwellt y Defaid | Festuca ovina |
| All names | Peisgwellt y Defaid | Festuca ovina |
| All names | Peisgwellt y Fagwyr | Vulpia myuros |
| All names | Peisgwellt y Waun | Festuca pratensis |
| All names | Peisgwellt y Waun | Festuca ovina |
| All names | Peisgwellt Ymdaenol | Festuca rubra |
| All names | Peisgwyn | Populus alba |
| All names | Pelanllys | Pilularia globulifera |
| All names | Pelanllys Gronynnog | Pilularia globulifera |
| All names | Pelydr Du | Helleborus niger |
| All names | Pelydr Gau Ysbaen | Peucedanum ostruthium |
| All names | Pelydr Gwyrdd | Helleborus viridis |
| All names | Pelydr y Cerrig | Parietaria judaica |
| All names | Pelydr y Gwelydd | Parietaria judaica |
| All names | Pen Melfed | Typha latifolia |
| All names | Penboeth | Galeopsis tetrahit |
| All names | Penboeth Gulddail | Galeopsis angustifolia |
| All names | Penddu | Gnaphalium uliginosum |
| All names | Peneuraid | Ranunculus auricomus |
| All names | Penfelen | Senecio vulgaris |
| All names | Penfelen | Senecio jacobaea |
| All names | Penfelen Fenyw | Senecio vulgaris |
| All names | Penfelen Fynyddol | Senecio sylvaticus |
| All names | Penfelen Ledlwyd | Senecio erucifolius |
| All names | Penfelen y Gors | Senecio aquaticus |
| All names | Pengaled | Centaurea |
| All names | Pengaled | Centaurea nigra |
| All names | Pengaled | Centaurea nigra |
| All names | Pengaled Benddu | Centaurea nigra |
| All names | Pengaled Benddu | Centaurea nigra |
| All names | Pengaled Fwyaf | Centaurea scabiosa |
| All names | Pengaled Leiaf Benddu | Centaurea nigra |
| All names | Pengaled Leiaf Benddu | Centaurea nigra |
| All names | Pengaled Lwytgoch | Centaurea jacea |
| All names | Pengaled Mawr | Centaurea scabiosa |
| All names | Pengoch | Polygonum amphibium |
| All names | Pengron Wen | Brassica oleracea |
| All names | Penigan | Dianthus |
| All names | Penigan Cyffredin | Dianthus plumarius |
| All names | Penigan Gwyryfaidd | Dianthus deltoides |
| All names | Penigan Rhuddgoch | Dianthus grantianopolitanus |
| All names | Penigan y Porfeydd | Dianthus armeria |
| All names | Penlas | Jovibarba sobolifera |
| All names | Penlas yr ꤼ/TD> | Centaurea cyanus |
| All names | Penllwyd | Filago germanica |
| All names | Penllwyd | Gnaphalium uliginosum |
| All names | Pennau'r Gŵyr | Plantago lanceolata |
| All names | Pennau'r Gwŷr | Potentilla reptans |
| All names | Penrhudd | Origanum vulgare |
| All names | Pensag | Humulus lupulus |
| All names | Pensoeg | Humulus lupulus |
| All names | Peny Neidr | Viola canina |
| All names | Peradyl | Leontodon autumnalis |
| All names | Peradyl Cynaeafol | Leontodon autumnalis |
| All names | Peradyl Garw | Leontodon hispidus |
| All names | Peradyl Gwanwynol | Leontodon autumnalis |
| All names | Peradyl yr Hydref | Leontodon autumnalis |
| All names | Perbren | Pyrus communis |
| All names | Perchwerwyn | Marrubium vulgare |
| All names | Perfagl | Vinca minor |
| All names | Perfagl Mwyaf | Vinca major |
| All names | Perllys | Reseda lutea |
| All names | Perllys Cyffredin | Petroselinum crispum |
| All names | Perllys y Morfa | Apium graveolens |
| All names | Perllys y Perthi | Chaerophyllum temulentum |
| All names | Persli | Petroselinum crispum |
| All names | Persli'r Ffŵl | Aethusa cynapium |
| All names | Persli'r Ffŵl | Aethusa cynapium |
| All names | Persli'r Meirch | Ligusticum scoticum |
| All names | Perthlys | Bilderdykia convolvulus |
| All names | Perwellt | Anthoxanthum odoratum |
| All names | Perwraidd | Astragalus glycyphyllos |
| All names | Perwydden | Pyrus communis |
| All names | Pibennog | Eriocaulon septangulare |
| All names | Pibfrwyn | Schoenus nigricans |
| All names | Piblys | Descurainia sophia |
| All names | Pidyn fy Modryb | Sedum reflexum |
| All names | Pidyn y Gog | Arum maculatum |
| All names | Pig Aran y Weirglodd | Geranium pratense |
| All names | Pig y Bwn | Equisetum fluviatile |
| All names | Pig y Crêyr | Erodium cicutarium |
| All names | Pig y Crêyr Cegidaidd | Erodium cicutarium |
| All names | Pig y Crêyr Mwsgaidd | Erodium moschatum |
| All names | Pig y Gog | Arum maculatum |
| All names | Pig yr Aran | Geranium pratense |
| All names | Pig yr Aran Clymog | Geranium nodosum |
| All names | Pig yr Aran Crynddail | Geranium rotundifolium |
| All names | Pig yr Aran Disglair | Geranium lucidum |
| All names | Pig yr Aran Droed-rudd | Geranium robertianum |
| All names | Pig yr Aran Dulwyd | Geranium phaeum |
| All names | Pig yr Aran Gyffredin | Geranium molle |
| All names | Pig yr Aran Llarpiog | Geranium dissectum |
| All names | Pig yr Aran Mânflodeuog | Geranium pusillum |
| All names | Pig yr Aran Rhuddgoch | Geranium sanguineum |
| All names | Pig yr Aran y Coed | Geranium sylvaticum |
| All names | Pig yr Aran y Weirglodd | Geranium sylvaticum |
| All names | Pigl | Cynoglossum officinale |
| All names | Pigyl | Cynoglossum officinale |
| All names | Pigyl Meddygol | Cynoglossum officinale |
| All names | Pinc | Dianthus |
| All names | Pinwydden Arfor | Pinus pinaster |
| All names | Pinwydden Awstria | Pinus nigra |
| All names | Pinwydden Sgotland | Pinus sylvestris |
| All names | Pinwydden Wyllt | Pinus sylvestris |
| All names | Piswydden | Euonymus europaeus |
| All names | Plu'r Gwenunydd | Eriophorum angustifolium |
| All names | Plu'r Gwenunydd Culddail Cyffredin | Eriophorum angustifolium |
| All names | Plu'r Gweunydd Llydanddail | Eriophorum latifolium |
| All names | Plu'r Gweunydd Unben | Eriophorum vaginatum |
| All names | Plucen | Anthyllis vulneraria |
| All names | Plucen Fechan | Anthyllis vulneraria |
| All names | Poerlys | Peucedanum ostruthium |
| All names | Poethfflam | Ranunculus flammula |
| All names | Poethwraidd | Peucedanum ostruthium |
| All names | Polypodium | Polypodium vulgare |
| All names | Ponar | Vicia faba |
| All names | Poplar | Populus tremula |
| All names | Poplysen | Populus alba |
| All names | Poplysen Lombardi | Populus pyramidalis |
| All names | Poplysen Wen | Populus alba |
| All names | Popsylen Ddu | Populus nigra |
| All names | Popsylen Gilead | Populus gileadensis |
| All names | Porpin | Lythrum portula |
| All names | Pren Afalau | Malus sylvestris |
| All names | Pren Bocys | Buxus sempervirens |
| All names | Pren Ceri | Sorbus aucuparia |
| All names | Pren Ceri | Mespilus germanica |
| All names | Pren Crabas | Malus sylvestris |
| All names | Pren Criafol | Sorbus aucuparia |
| All names | Pren Melyn | Berberis vulgaris |
| All names | Pren-awyr | Viscum album |
| All names | Pren-yw | Taxus baccata |
| All names | Pryfet | Ligustrum vulgare |
| All names | Pryseg | Ruscus aculeatus |
| All names | Puburllys Culddail | Lepidium ruderale |
| All names | Puburllys Llydanddail | Lepidium latifolium |
| All names | Puburlys | Lepidium latifolium |
| All names | Pumbys | Potentilla reptans |
| All names | Pumbys yr Alban | Sibbaldia procumbens |
| All names | Pumdalen Gyffredin | Potentilla reptans |
| All names | Pumdalen y Gors | Potentilla palustris |
| All names | Pumdalen y Gwanwyn | Potentilla tabernaemontani |
| All names | Pumdalen Ymlusgol | Potentilla reptans |
| All names | Pumnalen Gyffredin Ymlusgaidd | Potentilla reptans |
| All names | Pumnalen Ymlusgaidd | Potentilla anglica |
| All names | Pupur Fint | Mentha spicata |
| All names | Pupur y Fawygr | Sedum acre |
| All names | Pupur-fintys | Mentha piperata |
| All names | Pupurlys Llwyd | Cardaria draba |
| All names | Purpur y Ddaear | Pilularia globulifera |
| All names | Pwff Mwg | Fumaria officinalis |
| All names | Pwmpleren | Populus nigra |
| All names | Pwpleren | Populus nigra |
| All names | Pwrpin | Lythrum portula |
| All names | Pwrs y Bugail | Capsella bursa-pastoris |
| All names | Pys y Ceirw | Lotus corniculatus |
| All names | Pys y Coed | Bryonia dioica |
| All names | Pysen y Ceirw Eiddilaidd | Lotus angustissimus |
| All names | Pysen y Ceirw Flewog | Lotus hispidus |
| All names | Pysen y Ceirw Mwyaf | Lotus uliginosus |
| All names | Pysen y Coed | Lathyrus montanus |
| All names | Pysen y Coed | Vicia orobus |
| All names | Pysen y Coed Ddu | Lathyrus niger |
| All names | Pysen y Coed Gnapwreiddiog | Lathyrus montanus |
| All names | Pysen y Garanod | Vicia |
| All names | Pysen yr Adar | Vicia |
| All names | Pysen yr Aran | Vicia |
| All names | Pyswydden | Laburnum vulgare |
| All names | Radys | Raphanus sativus |
| All names | Redis | Raphanus sativus |
| All names | Redyns | Raphanus sativus |
| All names | Rêp | Brassica napus var. oleifera |
| All names | Rhafnwydden | Rhamnus catharticus |
| All names | Rhanwellt y Cadno Cymalog | Alopecurus geniculatus |
| All names | Rhawn | Equisetum |
| All names | Rhawn March y Gors | Equisetum palustre |
| All names | Rhawn March yr Ardir | Equisetum arvense |
| All names | Rhawn y Afon | Equisetum fluviatile |
| All names | Rhawn y Coed | Equisetum sylvaticum |
| All names | Rhawn y Gaseg | Hippuris vulgaris |
| All names | Rhawn y Gors | Equisetum palustre |
| All names | Rhawn y March | Equisetum |
| All names | Rhawn y March Afonol | Equisetum fluviatile |
| All names | Rhawn yr Ardir | Equisetum arvense |
| All names | Rhedyn Cyffredin | Pteridium aquilinum |
| All names | Rhedyn Gwib | Blechnum spicant |
| All names | Rhedyn ungoes | Pteridium aquilinum |
| All names | Rhedyn y Cadno | Dryopteris filix-mas |
| All names | Rhedyn y Clogwyn | Asplenium septentrionale |
| All names | Rhedyn y Derw | Polypodium vulgare |
| All names | Rhedyn y Fagwyr | Polypodium vulgare |
| All names | Rhedyn y Gogofau | Phyllitis scolopendrium |
| All names | Rhedyn y Graig | Asplenium septentrionale |
| All names | Rhedyn y Mur | Asplenium ruta-muraria |
| All names | Rhedynach | Hymenophyllum tunbridgense |
| All names | Rhedynach teneuwe | Hymenophyllum tunbridgense |
| All names | Rhedynen Fair | Dryopteris oreopteris |
| All names | Rhedynen Gyfrdwy | Osmunda regalis |
| All names | Rhedynen y Cadno | Dryopteris filix-mas |
| All names | Rhodell | Typha angustifolia |
| All names | Rhodell | Typha latifolia |
| All names | Rhododendron | Rhododendron ponticum |
| All names | Rhodri | Raphanus sativus |
| All names | Rhogai | Chenopodium vulvaria |
| All names | Rhoglus | Chenopodium vulvaria |
| All names | Rholbren | Typha angustifolia |
| All names | Rholbryn | Typha latifolia |
| All names | Rhonell y March | Equisetum |
| All names | Rhonwellt | Phleum pratense |
| All names | Rhonwellt Cadno'r Weirglodd | Alopecurus pratensis |
| All names | Rhonwellt y Cadno | Alopecurus |
| All names | Rhonwellt y Ci | Cynosurus cristatus |
| All names | Rhonwellt y Ci Cribog | Cynosurus cristatus |
| All names | Rhonwellt y Ci Cribog | Cynosurus cristatus |
| All names | Rhonwellt y Gath | Phleum pratense |
| All names | Rhonwellt y Gath Gyffredin | Phleum pratense |
| All names | Rhonwellt y Tywyn | Phleum arenarium |
| All names | Rhôs | Rosa |
| All names | Rhosgampau | Verbascum thapsus |
| All names | Rhoslwyn Pêr | Rosa micrantha |
| All names | Rhoslwyn Pêr | Rosa rubiginosa agg. |
| All names | Rhosmair gwyllt | Andromeda polifolia |
| All names | Rhosmari Gwyllt | Andromeda polifolia |
| All names | Rhoswydd | Rosa |
| All names | Rhosyn Bach y Gwynt (Almaen) | Anemone nemorosa |
| All names | Rhosyn Burnet | Rosa spinosissima |
| All names | Rhosyn Coch Gwyllt | Rosa canina |
| All names | Rhosyn Gwlanog | Rosa villosa |
| All names | Rhosyn Gwyllt | Rosa canina |
| All names | Rhosyn Gwyn Gwyllt | Rosa arvensis |
| All names | Rhosyn lled-wlanog | Rosa tomentosa agg. |
| All names | Rhosyn Lledwlanog | Rosa villosa |
| All names | Rhosyn Saron | Hypericum calycinum |
| All names | Rhosyn y Cŵn | Rosa canina |
| All names | Rhosyn y Mynydd | Paeonia mascula |
| All names | Rhuddlas y Gors | Caltha palustris |
| All names | Rhuddos | Chrysanthemum segetum |
| All names | Rhuddos y Gors | Chrysanthemum segetum |
| All names | Rhuddos y Gors | Caltha palustris |
| All names | Rhuddwernen | Prunus padus |
| All names | Rhuddygl | Raphanus raphanistrum |
| All names | Rhuddygl | Raphanus sativus |
| All names | Rhuddygl Gwyllt | Raphanus raphanistrum |
| All names | Rhuddygl y Meirch | Armoracia rusticana |
| All names | Rhuddygyl Mawrth | Armoracia rusticana |
| All names | Rhwnen | Pyrus communis |
| All names | Rhwningbren | Pyrus communis |
| All names | Rhwningwydd | Pyrus communis |
| All names | Rhwnynen | Pyrus communis |
| All names | Rhwyddlwyn | Veronica |
| All names | Rhwyddlwyn Blewynnog | Veronica chamaedrys |
| All names | Rhwyddlwyn Culddail y Gors | Veronica scutellata |
| All names | Rhwyddlwyn Ddaileiddew | Veronica hederifolia |
| All names | Rhwyddlwyn Eiddewddail | Veronica hederifolia |
| All names | Rhwyddlwyn Gorweddol | Veronica agrestis |
| All names | Rhwyddlwyn Gwrywddail | Veronica serpyllifolia |
| All names | Rhwyddlwyn Gwyrdd Gorweddol | Veronica agrestis |
| All names | Rhwyddlwyn Meddygol | Veronica officinalis |
| All names | Rhwyddlwyn Mynyddig | Veronica montana |
| All names | Rhwyddlwyn Mynyddol | Veronica montana |
| All names | Rhwyddlwyn y Ddeilen Ddu Dda | Veronica chamaedrys |
| All names | Rhwyddlwyn y Mur | Veronica arvensis |
| All names | Rhwymyn y Coed | Tamus communis |
| All names | Rhyddygl Poeth | Armoracia rusticana |
| All names | Rhyfon Coch | Ribes rubrum |
| All names | Rhyfon Duon | Ribes nigrum |
| All names | Rhyfon mynydd | Ribes alpinum |
| All names | Rhyfwydden Ddu | Ribes nigrum |
| All names | Rhyfwydden Fynyddol | Ribes alpinum |
| All names | Rhyg | Secale cereale |
| All names | Rhygwellt | Lolium perenne |
| All names | Rhygwellt Eidalaidd | Lolium multiflorum |
| All names | Rhygwellt Lluosflwydd | Lolium perenne |
| All names | Rhyswydden | Ligustrum vulgare |
| All names | Rhyw'r Muriau | Asplenium ruta-muraria |
| All names | Robin Fratiog | Lychnis flos-cuculi |
| All names | Rotbolia | Parapholis strigosa |
| All names | Rwpia Morol | Ruppia maritima |
| All names | Rwpia'r Môr | Ruppia maritima |
| All names | Saethbennig Arfor | Triglochin maritimum |
| All names | Saethbennig y Gors | Triglochin palustre |
| All names | Saethbennig y Morfa | Triglochin maritimum |
| All names | Saethlys | Sagittaria sagittifolia |
| All names | Saethlys saethffeilaidd | Sagittaria sagittifolia |
| All names | Saets Gwyllt | Salvia verbenacea |
| All names | Saets Gwyllt | Teucrium chamaedrys |
| All names | Saets Gwyllt | Teucrium scorodonia |
| All names | Saets y Waun | Salvia pratensis |
| All names | Saffrwm noeth-flodeuog | Crocus nudiflorus |
| All names | Saffrwm y Gweunydd | Colchicum autumnale |
| All names | Safn y Llew | Antirrhinum majus |
| All names | Safri | Satureja montana |
| All names | Safri Fach | Satureja montana |
| All names | Samlyen | Samolus valerandi |
| All names | Sampier | Crithmum maritimum |
| All names | Sampier y Defaid | Plantago maritima |
| All names | Sampier y Geifr | Inula crithmoides |
| All names | Samwl | Samolus valerandi |
| All names | Sarff | Sorbus aucuparia |
| All names | Sarffwydden | Sorbus aucuparia |
| All names | Sataen | Castanea sativa |
| All names | Sawdl Crist | Plantago lanceolata |
| All names | Sawdl Crist | Plantago major |
| All names | Sawdl y crydd | Chenopodium bonus-henricus |
| All names | Sawdl y Crydd | Chenopodium bonus-henricus |
| All names | Sawdl y Crydd | Chenopodium aristatum |
| All names | Sawdl y Crydd | Mercurialis perennis |
| All names | Sawdl y Fuwch | Primula veris |
| All names | Sawdl y Fuwch | Caltha palustris |
| All names | Sbigfrwynen Gadeiriog | Eleocharis multicaulis |
| All names | Sbigfrwynen Goch | Eleocharis quinqueflora |
| All names | Sbigfrwynen Leiaf | Eleocharis acicularis |
| All names | Sbigfrwynen y Gors | Eleocharis palustris |
| All names | Sbriwsen Norwy | Picea abies |
| All names | Sbriwsen Sitka | Picea sitchensis |
| All names | Sebonllys | Saponaria officinalis |
| All names | Sebonllys meddygol | Saponaria officinalis |
| All names | Seifys | Allium schoenoprasum |
| All names | Seithnalen | Potentilla erecta |
| All names | Sêl Selyf | Polygonatum multiflorum |
| All names | Sêl Selyf Culddail | Polygonatum verticillatum |
| All names | Selidon | Chelidonium majus |
| All names | Senseg (Sir Frycheiniog) | Chrysanthemum segetum |
| All names | Sensigl | Leucanthemum vulgare |
| All names | Seraidd Ysgallen | Centaurea calcitrapa |
| All names | Serellys y Morfa | Aster tripolium |
| All names | Seren Bethlehem | Ornithogalum umbellatum |
| All names | Seren Fethlehem Gyffredin | Ornithogalum umbellatum |
| All names | Seren Fethlehem Hir | Ornithogalum pyrenaicum |
| All names | Seren y Gwanwyn | Scilla verna |
| All names | Seren y Gwanwyn | Ranunculus ficaria |
| All names | Seren yr Hydref | Scilla autumnalis |
| All names | Serenllys | Stellaria |
| All names | Serenllys Mawr | Stellaria holostea |
| All names | Serennyn | Scilla verna |
| All names | Serennyn y Gwanwyn | Scilla verna |
| All names | Sesleria | Sesleria caerulea |
| All names | Sewyrllys | Satureja montana |
| All names | Sgorpion y Coed | Myosotis sylvatica |
| All names | Sherardia | Sherardia arvensis |
| All names | Sherardia Glas | Sherardia arvensis |
| All names | Siani Lusg | Lysimachia nummularia |
| All names | Sibaldia | Potentilla reptans |
| All names | Sibthorpia | Sibthorpia europaea |
| All names | Sidan y Waun | Eriophorum angustifolium |
| All names | Sidan y Waun Llydanddail | Eriophorum latifolium |
| All names | Sidwrmot | Artemisia campestris |
| All names | Simwr y Côr | Alchemilla vulgaris |
| All names | Sinsir y Gors | Peucedanum ostruthium |
| All names | Sircyn y Melinydd | Verbascum nigrum |
| All names | Sircyn y Melinydd | Verbascum thapsus |
| All names | Sirianen | Prunus cerasus |
| All names | Sirianen Ddu | Prunus avium |
| All names | Sisli Bêr | Myrrhis odorata |
| All names | Siwdr | Artemisia campestris |
| All names | Smalaes | Apium graveolens |
| All names | Sugn y Geifr | Lonicera periclymenum |
| All names | Sugr y Geifr | Lonicera periclymenum |
| All names | Suran Deirdalen | Oxalis acetosella |
| All names | Suran Hir | Rumex hydrolapathum |
| All names | Suran y Coed | Oxalis acetosella |
| All names | Suran y Coed Felen Orweddol | Oxalis corniculata |
| All names | Suran y Cŵn | Rumex acetosa |
| All names | Suran y Frân | Rumex acetosa |
| All names | Suran y Gog | Oxalis acetosella |
| All names | Suran y Maes | Rumex acetosa |
| All names | Suran y Mynydd | Oxyria digyna |
| All names | Suran y Waun | Rumex acetosa |
| All names | Suran yr ꤼ/TD> | Rumex acetosella |
| All names | Sweds | Brassica napus var. oleifera |
| All names | Swllt Dyn Tlawd | Lunaria annua |
| All names | Swp-hesgen y Fawnog | Carex nigra |
| All names | Swyn esgras | Chrysanthemum segetum |
| All names | Swynfri | Bellis perennis |
| All names | Sycamorwydden | Acer pseudoplatanus |
| All names | Syfîen (De Cymru) | Fragaria |
| All names | Symylen | Primula veris |
| All names | Tafod y Bwch | Echium vulgare |
| All names | Tafod y Bytheiad | Cynoglossum officinale |
| All names | Tafod y Bytheiad Gwyrdd-ddail | Cynoglossum germanicum |
| All names | Tafod y Bytheiad Meddygol | Cynoglossum officinale |
| All names | Tafod y Ci | Potamogeton natans |
| All names | Tafod y Ci | Cynoglossum officinale |
| All names | Tafod y Fuwch | Borago officinalis |
| All names | Tafod y Gors | Pinguicula vulgaris |
| All names | Tafod y Llew | Picris echioides |
| All names | Tafod y neidr | Ophioglossum vulgatum |
| All names | Tafod yr Afr | Echium vulgare |
| All names | Tafod yr Edn | Stellaria |
| All names | Tafod yr Edn Lleiaf | Stellaria graminea |
| All names | Tafod yr Edn Llwydlas | Stellaria palustris |
| All names | Tafod yr Edn Mwyaf | Stellaria holostea |
| All names | Tafod yr Edn Mynyddig | Cerastium cerastoides |
| All names | Tafod yr Edn y Goedwig | Stellaria nemorum |
| All names | Tafod yr Edn y Gors | Stellaria alsine |
| All names | Tafod yr Ehedydd | Consolida regalis |
| All names | Tafod yr Hydd Cyffredin | Phyllitis scolopendrium |
| All names | Tafod yr Iâr | Polygonum persicaria |
| All names | Tafod yr Oen | Chenopodium album |
| All names | Tafod yr Oen | Plantago media |
| All names | Tafod yr Ych | Borago officinalis |
| All names | Tafod yr Ych anwyw | Pentaglottis sempervirens |
| All names | Tafod yr Ych Culddail | Lychnis viscaria |
| All names | Tafod yr Ych lliwiol | Pentaglottis sempervirens |
| All names | Tafod yr Ych Meddygol | Lychnis viscaria |
| All names | Tafod yr �d | Achillea ptarmica |
| All names | Tafol Arfor | Rumex maritimus |
| All names | Tafol Coch | Rumex sanguineus |
| All names | Tafol Crych | Rumex crispus |
| All names | Tafol y Dŵr | Rumex hydrolapathum |
| All names | Tafol y Môr | Helleborus foetidus |
| All names | Tafolen | Rumex conglomeratus |
| All names | Tafolen Goch | Rumex sanguineus |
| All names | Tafolen Grych | Rumex crispus |
| All names | Tafolen Gyffredin | Rumex obtusifolius |
| All names | Tafolen Hir | Rumex hydrolapathum |
| All names | Tafolen Lydanddail | Rumex obtusifolius |
| All names | Tafolen Mair | Rumex conglomeratus |
| All names | Tafolen Waedlyd | Rumex sanguineus |
| All names | Tafolen y Cŵm | Rumex obtusifolius |
| All names | Tafolen y Dŵr | Rumex hydrolapathum |
| All names | Tafolen y Môr | Rumex maritimus |
| All names | Tafor yr Edn Canolig | Stellaria media |
| All names | Tag yr Aradr | Ononis repens |
| All names | Tagaradr | Ononis repens |
| All names | Taglys | Convulvulus arvensis |
| All names | Taglys Du | Tamus communis |
| All names | Taglys Mawr | Calystegia sepium |
| All names | Taglys yr ꤼ/TD> | Bilderdykia convolvulus |
| All names | Tagwydd | Calystegia sepium |
| All names | Tagwyg | Vicia cracca |
| All names | Tagwyg Bysen | Vicia cracca |
| All names | Talfedel | Angelica archangelica |
| All names | Tamaid y Cythraul | Succisa pratensis |
| All names | Tanclys | Tanacetum vulgare |
| All names | Tansi | Tanacetum vulgare |
| All names | Tansi Gwyllt | Potentilla anserina |
| All names | Tapr Dunos | Verbascum nigrum |
| All names | Tapr Dunos | Verbascum thapsus |
| All names | Tapr Mair | Verbascum nigrum |
| All names | Tapr Mair | Verbascum thapsus |
| All names | Tapr y Dŵr | Typha latifolia |
| All names | Tapr y Dŵr | Typha angustifolia |
| All names | Tarfgryd | Chrysanthemum parthenium |
| All names | Tarfwgan | Hypericum perforatum |
| All names | Tawddrudd Crynddail | Drosera rotundifolia |
| All names | Tawddrudd Hirddail | Drosera intermedia |
| All names | Tawddrudd Mawr | Drosera anglica |
| All names | Tegeirian Bera | Anacamptis pyramidalis |
| All names | Tegeirian Brych | Dactylorhiza maculata |
| All names | Tegeirian Brych Cyffredin | Dactylorhiza fuchsii |
| All names | Tegeirian Coch | Orchis mascula |
| All names | Tegeirian Coch y Gwanwyn | Orchis mascula |
| All names | Tegeirian Coch yr Haf | Anacamptis pyramidalis |
| All names | Tegeirian Ddwy-ddalennog | Platanthera bifolia |
| All names | Tegeirian Dwyddalennog | Platanthera bifolia |
| All names | Tegeirian Gŵr | Aceras anthropophorum |
| All names | Tegeirian Llydanwyrdd | Platanthera chlorantha |
| All names | Tegeirian Lydanwyrdd Bach | Platanthera bifolia |
| All names | Tegeirian Mannog Byseddog | Dactylorhiza fuchsii |
| All names | Tegeirian Mannog Byseddog | Dactylorhiza maculata |
| All names | Tegeirian Nyth Aderyn | Neottia nidus-avis |
| All names | Tegeirian per | Gymnadenia conopsea |
| All names | Tegeirian Pêr | Gymnadenia conopsea |
| All names | Tegeirian peraroglaidd | Gymnadenia conopsea |
| All names | Tegeirian peraroglaidd | Gymnadenia conopsea |
| All names | Tegeirian Porffor | Orchis mascula |
| All names | Tegeirian Pryfyn | Ophrys insectifera |
| All names | Tegeirian y Fign | Liparis loeselii |
| All names | Tegeirian y Gors | Dactylorhiza sambucina |
| All names | Tegeirian y Gwenyn | Ophrys apifera |
| All names | Tegeirian y Waun | Orchis morio |
| All names | Tegeirian Ynfytyn | Orchis morio |
| All names | Tegwch Meinwen | Ononis repens |
| All names | Teilai Gwyllt | Dipsacus laciniatus |
| All names | Teilai Mawr | Dipsacus fullonum |
| All names | Teim | Thymus |
| All names | Teim Gwyllt | Thymus serpyllum |
| All names | Teircaill | Spiranthes spiralis |
| All names | Tethi'r Gaseg | Lonicera periclymenum |
| All names | Tewbannog | Verbascum nigrum |
| All names | Tewbannog | Verbascum thapsus |
| All names | Tewbanog Fechan | Primula vulgaris |
| All names | Tinagored | Mespilus germanica |
| All names | Tinboeth | Polygonum hydropiper |
| All names | Tindoll | Mespilus germanica |
| All names | Tinllwyd | Potentilla anserina |
| All names | Tinllwyd | Potentilla reptans |
| All names | Tiwlip Gwyllt | Tulipa silvestris |
| All names | Toddaiadd Cyffredin | Pinguicula vulgaris |
| All names | Toddaid Wen | Hydrocotyle vulgaris |
| All names | Toddaidd Melyn Cyffredin | Pinguicula vulgaris |
| All names | Toddaidrudd | Drosera rotundifolia |
| All names | Toddedig Felen | Pinguicula vulgaris |
| All names | Toddedig Wen | Hydrocotyle vulgaris |
| All names | Tofagl | Euphrasia stricta |
| All names | Torfagl | Salvia verbenacea |
| All names | Torllwyd | Hieracium pilosella |
| All names | Torllwyd | Hieracium |
| All names | Torllwydig | Hieracium pilosella |
| All names | Torllwydig | Hieracium pilosella |
| All names | Torllwydig | Hieracium |
| All names | Tormaen | Saxifraga |
| All names | Tormaen Blewog Dail Hirgrwm | Saxifraga hirsuta |
| All names | Tormaen Burnet | Pimpinella saxifraga |
| All names | Tormaen Crwn Gogwyddol | Saxifraga cernua |
| All names | Tormaen Crymddail | Saxifraga rosacea |
| All names | Tormaen Cyferbynddail | Saxifraga oppositifolia |
| All names | Tormaen Elwlenddail | Saxifraga hirsuta |
| All names | Tormaen Glasgoch | Saxifraga oppositifolia |
| All names | Tormaen Gwyn | Saxifraga granulata |
| All names | Tormaen Llydandroed | Saxifraga hypnoides |
| All names | Tormaen Melyn Mynyddig | Saxifraga aizoon |
| All names | Tormaen Melyn y Gors | Saxifraga hirculus |
| All names | Tormaen Mwsoglaidd | Saxifraga hypnoides |
| All names | Tormaen Mynyddig Blewog | Saxifraga rosacea |
| All names | Tormaen Mynyddig Sypiog | Saxifraga nivalis |
| All names | Tormaen Mynyddig y Ffrwd | Saxifraga rivularis |
| All names | Tormaen Mynyddig Ymylgrych | Saxifraga rosacea |
| All names | Tormaen Serennog | Saxifraga stellaris |
| All names | Tormaen Siobynnog | Saxifraga cespitosa |
| All names | Tormaen Torwenwynddail | Saxifraga tridactylites |
| All names | Tormaen Tribys | Saxifraga tridactylites |
| All names | Tormwyth | Chrysanthemum parthenium |
| All names | Tostfrwynen | Scirpus lacustris |
| All names | Tostfrwynen arfor | Scirpus tabernaemontani |
| All names | Traeturiaid y Bugeilydd | Potentilla reptans |
| All names | Traeturiaid y Bugeilydd | Plantago lanceolata |
| All names | Tresgl Melyn | Potentilla erecta |
| All names | Tresgl y Moch | Potentilla erecta |
| All names | Tresgl Ymlusgaidd | Potentilla anglica |
| All names | Tresgl yr Eithin | Potentilla erecta |
| All names | Tresi Aur | Laburnum vulgare |
| All names | Trewynwyn y Goedwig | Lysimachia nemorum |
| All names | Trewynyn | Lysimachia vulgaris |
| All names | Trewynyn Cyffredin | Lysimachia vulgaris |
| All names | Trewynyn sypflodeuog | Lysimachia thyrsiflora |
| All names | Triagl Tair Dalen | Oxalis acetosella |
| All names | Triagl y Cymro | Teucrium scorodonia |
| All names | Triaglog | Valeriana officinalis |
| All names | Triaglog Bychan y Gors | Valeriana dioica |
| All names | Triaglog Coch | Centranthus ruber |
| All names | Triaglog y Gors | Valeriana dioica |
| All names | Trilliw (Cwm Penmachno) | Viola tricolor |
| All names | Trilliw yr Âr | Viola arvensis |
| All names | Troed y Barcud | Thalictrum alpinum |
| All names | Troed y Ceiliog | Dactylis glomerata |
| All names | Troed y Deryn | Lotus corniculatus |
| All names | Troed y Dryw | Aphanes arvensis |
| All names | Troed y Gath | Antennaria dioica |
| All names | Troed y Golomen | Geranium molle |
| All names | Troed y Golomen | Aquilegia vulgaris |
| All names | Troed y Gywen | Lythrum portula |
| All names | Troed yr Aderyn | Ornithopus perpusillus |
| All names | Troed yr Arth | Helleborus foetidus |
| All names | Troed yr Asen | Alliaria petiolata |
| All names | Troed yr Ebol | Caltha palustris |
| All names | Troed yr Ehedydd | Consolida regalis |
| All names | Troed yr Eryr | Ranunculus scleratus |
| All names | Troed yr Wŷdd Arfor | Suaeda maritima |
| All names | Troed yr ŵydd llios-hadog | Chenopodium polyspermum |
| All names | Troed yr Ysgyfarnog | Trifolium arvense |
| All names | Troed yr �d | Chenopodium |
| All names | Troed yr �d | Chenopodium album |
| All names | Troed yr �d Arforol | Chenopodium rubrum |
| All names | Troed yr �d Dderw-ddeiliog | Chenopodium glaucum |
| All names | Troed yr �d Ddynad-ddail | Chenopodium murale |
| All names | Troed yr �d Ffigys-ddail | Chenopodium ficifolium |
| All names | Troed yr �d Gwynaidd | Chenopodium album |
| All names | Troed yr �d Lios-sypiog | Chenopodium botryodes |
| All names | Troed yr �d Masarndaill | Chenopodium hybridum |
| All names | Troed yr �d Ruddog | Chenopodium rubrum |
| All names | Troed yr �d Syth-ddail | Chenopodium urbicum |
| All names | Troed-y-cyw Clymog | Torilis nodosa |
| All names | Troed-y-cyw Syth | Torilis japonica |
| All names | Troed-y-cyw Ymdaenol | Torilis arvensis |
| All names | Troellgorun | Juncus squarrosus |
| All names | Troellig | Spergula arvensis |
| All names | Troellig Clymog | Sagina nodosa |
| All names | Troellig Mwyaf | Spergula arvensis |
| All names | Troellig Mynawydaidd Crych | Sagina saginoides |
| All names | Troellig yr ꤼ/TD> | Spergula arvensis |
| All names | Troellys Coch | Spergularia rubra |
| All names | Troellys Mawr | Spergularia marginata |
| All names | Trwyn y Llo | Misopates orontium |
| All names | Trwyn y Llo Blaenfeinddail | Kickxia elatine |
| All names | Trwyn y Llo Bychan | Misopates orontium |
| All names | Trwyn y Llo Eiddewddail | Cymbalaria muralis |
| All names | Trwyn y Llo Mwyaf | Antirrhinum majus |
| All names | Trwynsor | Chenopodium vulvaria |
| All names | Trydon | Agrimonia eupatoria |
| All names | Trython | Rumex conglomeratus |
| All names | Tryw | Agrimonia eupatoria |
| All names | Tusw Dyfrllys | Ruppia maritima |
| All names | Tusw Dyfrllys | Ruppia maritima |
| All names | Twrged Blewog | Arabis hirsuta |
| All names | Twrged Esmwyth | Turritis glabra |
| All names | Tylwyth y Lili | Gagea lutea |
| All names | Tywodlydd Glasrudd | Spergularia rubra |
| All names | Tywodlys Arfor | Honkenya peploides |
| All names | Tywodlys Trinerf | Moehringia trinervia |
| All names | Tywodlys y Gwanwyn | Minuartia verna |
| All names | Tywodwlydd | Arenaria serpyllifolia |
| All names | Tywodwlydd Arfor | Honkenya peploides |
| All names | Tywodwlydd Bychan Coch | Minuartia rubella |
| All names | Tywodwlydd Gwanwynol | Minuartia verna |
| All names | Tywodwlydd gwrywddail | Arenaria serpyllifolia |
| All names | Tywodwlydd llyriad-ddail | Moehringia trinervia |
| All names | Uchelawr | Viscum album |
| All names | Uchelfa | Viscum album |
| All names | Uchelfar | Viscum album |
| All names | Uchelfel | Viscum album |
| All names | Uchelog | Viscum album |
| All names | Uchelwydd | Viscum album |
| All names | Wdron | Galium odoratum |
| All names | Wermod | Artemisia absinthium |
| All names | Wermod Lwyd | Artemisia absinthium |
| All names | Wermod Wen | Chrysanthemum parthenium |
| All names | Wermod y Môr | Artemisia maritima |
| All names | Wermod y Môr Ogwydd Flodeuog | Artemisia maritima |
| All names | Wroith | Tanacetum vulgare |
| All names | Wynionyn | Allium cepa |
| All names | Wyniwyn | Allium cepa |
| All names | Wynwyn | Allium cepa |
| All names | Y Benboeth Amryliw | Galeopsis speciosa |
| All names | Y Bengaled | Centaurea cyanus |
| All names | Y Benlas Wen | Centaurea cyanus |
| All names | Y Besychlys | Tussilago farfara |
| All names | Y Brefai | Mentha pulegium |
| All names | Y Breflys | Mentha pulegium |
| All names | Y Chwerwddŵr | Artemisia absinthium |
| All names | Y Cyngaf Lleiaf | Arctium minus |
| All names | Y Dderwen Fendigaid | Verbena officinalis |
| All names | Y Ddiwlith | Chelidonium majus |
| All names | Y Dewbannog Fechan | Primula veris |
| All names | Y Dorllwyn | Potentilla anserina |
| All names | Y Dowrudd | Geranium pratense |
| All names | Y Drydon | Agrimonia eupatoria |
| All names | Y Fedwen Arian | Betula pendula |
| All names | Y Felynllys | Galium verum |
| All names | Y Felynllys | Galium verum |
| All names | Y Felynllys | Potentilla reptans |
| All names | Y Felysig | Agrimonia eupatoria |
| All names | Y Fioled Fraith | Viola tricolor |
| All names | Y Fioled Fraith | Ranunculus ficaria |
| All names | Y Frithlys | Anemone nemorosa |
| All names | Y Frithogen | Anemone nemorosa |
| All names | Y Fronwys | Ranunculus ficaria |
| All names | Y Fywlwys | Ranunculus ficaria |
| All names | Y Ganrhi Felen | Blackstonia perfoliata |
| All names | Y Ganrhi Goch | Centaurium minus |
| All names | Y Ganrhi Goch Arfor | Centaurium littorale |
| All names | Y Gingroen Fechan | Linaria vulgaris |
| All names | Y Glafrlys | Centaurea cyanus |
| All names | Y Goesgoch | Geranium robertianum |
| All names | Y Goesgoch | Geranium pratense |
| All names | Y Gorfedwen | Betula nana |
| All names | Y Gramennog | Centaurea nigra |
| All names | Y Gramennog | Centaurea cyanus |
| All names | Y Gramennog Fawr | Centaurea scabiosa |
| All names | Y Gromadni | Lithospermum officinale |
| All names | Y Gynddal | Hypericum perforatum |
| All names | Y Pumnalen | Potentilla reptans |
| All names | Y Rhai Cyffredin | Lactuca sativa |
| All names | Y We Felen | Trifolium dubium |
| All names | Y Wialen Aur | Solidago virgaurea |
| All names | Y Wilffrai | Achillea millefolium |
| All names | Y Winwydden Wen | Bryonia dioica |
| All names | Yaig | Agrostemma githago |
| All names | Yr Helyglys | Lythrum salicaria |
| All names | Ysbeinwydden | Buxus sempervirens |
| All names | Ysbin | Berberis vulgaris |
| All names | Ysbyddaden | Crataegus laevigata |
| All names | Ysgall y Calch | Carlina vulgaris |
| All names | Ysgallen Benwlanog | Cirsium eriophorum |
| All names | Ysgallen Ddi-goes | Cirsium acaule |
| All names | Ysgallen Ddreinwen | Carlina vulgaris |
| All names | Ysgallen Fair | Silybum marianum |
| All names | Ysgallen Fân-flodeuog | Carduus tenuiflorus |
| All names | Ysgallen Flodfaen | Carduus tenuiflorus |
| All names | Ysgallen Foglymog | Eryngium maritimum |
| All names | Ysgallen Fraith | Silybum marianum |
| All names | Ysgallen Fwyth | Cirsium heterophyllum |
| All names | Ysgallen Ganpen | Eryngium planum |
| All names | Ysgallen Goch | Sonchus oleraceus |
| All names | Ysgallen Gotymog | Onopordum acanthium |
| All names | Ysgallen Gotymog | Onopordum acanthium |
| All names | Ysgallen Grych | Carduus crispus |
| All names | Ysgallen Gyffredin | Cirsium arvense |
| All names | Ysgallen Gyffredin yr Âr | Cirsium arvense |
| All names | Ysgallen Ogwydd | Carduus nutans |
| All names | Ysgallen Wen | Silybum marianum |
| All names | Ysgallen Wyllt | Cirsium vulgare |
| All names | Ysgallen y Blaidd | Cirsium vulgare |
| All names | Ysgallen y Gors | Cirsium palustre |
| All names | Ysgallen y Meirch | Cichorium intybus |
| All names | Ysgallen y Moch | Sonchus oleraceus |
| All names | Ysgallenllys | Plantago lanceolata |
| All names | Ysgaw Mair | Sambucus ebulus |
| All names | Ysgaw'r Ddaear | Sambucus ebulus |
| All names | Ysgaw(en) Fair | Sambucus ebulus |
| All names | Ysgawen | Sambucus nigra |
| All names | Ysgawen Bendiged | Sambucus ebulus |
| All names | Ysgawen Fendigaid | Sambucus ebulus |
| All names | Ysgawen y Gors | Viburnum opulus |
| All names | Ysgawlwyn Cyffredin | Sambucus nigra |
| All names | Ysgedd | Crambe maritima |
| All names | Ysgedd Arfor | Crambe maritima |
| All names | Ysgellog | Cichorium intybus |
| All names | Ysglarei | Salvia verbenacea |
| All names | Ysgol Crist | Centaurium minus |
| All names | Ysgol Crist | Hypericum perforatum |
| All names | Ysgol Fair | Centaurium minus |
| All names | Ysgol Fair | Hypericum perforatum |
| All names | Ysgol Jacob | Polemonium caeruleum |
| All names | Ysgordiwm | Teucrium chamaedrys |
| All names | Ysgorpionllys | Myosotis palustris |
| All names | Ysgorpionllys | Myosotis arvensis |
| All names | Ysgorpionllys amryliw | Myosotis discolor |
| All names | Ysgorpionllys Siobynnog | Myosotis caespitosa |
| All names | Ysgorpionllys y Coed | Myosotis sylvatica |
| All names | Ysgorpionllys y Creigiau | Myosotis alpestris |
| All names | Ysgorpionllys y Gors | Myosotis secunda |
| All names | Ysgorpionllys y Gors | Myosotis palustris |
| All names | Ysgorpionllys y Meysydd | Myosotis arvensis |
| All names | Ysgorpionllys y Meysydd | Myosotis palustris |
| All names | Ysgorpionllys Ymlusgaidd | Myosotis secunda |
| All names | Ysgras | Potentilla erecta |
| All names | Ysgyr | Teucrium chamaedrys |
| All names | Ysgyrfi Gwryw | Halimione portulacoides |
| All names | Ysgyrfi-lys Cyffredin | Cochlearia officinalis |
| All names | Ysgyrfi-lys Llychlyn | Cochlearia danica |
| All names | Ysgyrfi-lys Seisnig | Cochlearia anglica |
| All names | Ysgyrfi-lys Seisnig | Cochlearia anglica |
| All names | Ysniap | Brassica nigra |
| All names | Ysnoden Fair | Cyperus longus |
| All names | Ysnoden Fair Lwytgoch | Cyperus fuscus |
| All names | Ysnoden Laswerdd y Môr | Zostera marina |
| All names | Yspardun y Marchog | Consolida regalis |
| All names | Ysper-fintys | Mentha spicata |
| All names | Yspinwydden | Berberis vulgaris |
| All names | Yspinys | Berberis vulgaris |
| All names | Ysterwlys | Tanacetum vulgare |
| All names | Ystlys y Waun | Lotus corniculatus |
| All names | Ystrewlys | Achillea ptarmica |
| All names | Yswthornat | Artemisia campestris |
| All names | Yswydden Gyffredin | Ligustrum vulgare |
| All names | Yswynfri | Bellis perennis |
| All names | Ytag | Bilderdykia convolvulus |
| All names | Ytbysen | Lathyrus |
| All names | Ytbysen Barhaus Gulddail | Lathyrus sylvestris |
| All names | Ytbysen Barhaus Lydanddail | Lathyrus latifolius |
| All names | Ytbysen Coch | Lathyrus nissolia |
| All names | Ytbysen Felen | Lathyrus aphaca |
| All names | Ytbysen Flewgodog | Lathyrus hirsutus |
| All names | Ytbysen Las y Morfa | Lathyrus palustris |
| All names | Ytbysen y Ddôl | Lathyrus pratensis |
| All names | Ytbysen y Waun | Lathyrus pratensis |
| All names | Ytgeirch | Avena sativa |
| All names | Yw (lluosog) | Taxus baccata |
| All names | Ywen | Taxus baccata |
| All names | ꤠMeddw | Lolium temulentum |
