Run The Planet would like to thank Peter Bradley for helping to realize this English/Welsh running dictionary.
Able: Galluog.
To be able: Gallu/yn gallu.
Accelerate (to): Cyflymu (hyd/tuag at).
Advertisement: Hysbyseb.
Alcohol: Alcohol.
Agony: Poen.
Amateur: Amatur.
Ambition: Uchelgais.
Ambitious: Uchelgeisiol.
Ambulance: Ambiwlans.
Ankle: Migwrn.
Annual: (Yn) flynyddol.
Arch: Bwa.
Arch-support: Cynhaliaeth i fwa'r troed.
Arrow: Saeth.
Athlete: Athletwr.
Award: Gwobr.
Award ceremony: Seremoni wobrwyo.
Back: Cefn.
Bandage: Rhwymyn.
Band aid: Plastar.
Bathroom: Ystafell ymolchi/Ty bach.
Beat (to): Curo.
Best: (Y) gorau.
Better: Gwell.
Beverage: Diod.
Bike: Beic.
Bicycle: Beic.
Motorbike: Beic modur.
Blister: Swigen.
Blood: Gwaed.
Blood doping: Ychwanegu at gynnwys y gwaed.
Body: Corff.
Bone: Asgwrn.
Box: Blwch/bocs.
To box in: Cau i mewn.
Brace: Cynhelydd/par.
Break: Torri.
To break a bone: Torri asgwrn.
To take a break: Cymryd seibiant.
Breath: Anadl.
To breathe: Anadlu.
Bridge: Pont.
Bruise: Clais.
Calf: Cefn y goes.
Car: Car.
Carbohydrates: Carboheidredau.
Catch: Dal.
To catch up: Dal.
Category: Categori.
Challenge: Her.
To challenge: Herio.
Champion: Pencampwr(aig).
Change (to): Newid (i).
Changing area: Corlan newid.
Cheer: Bloedd.
To cheer: Calonogi.
City: Dinas.
Clap: Cymeradwyaeth/clap.
To clap: Cymeradwyo/clapio.
Classification: Dosbarth.
Climb: Rhiw.
To climb: Dringo.
Close: Cau/agos [near].
Closed: Yng nghau.
To close: Cau.
Coach: Hyfforddwr(aig).
To coach: Hyfforddi.
Cold: Oer/anwyd [the one you catch].
Color: Lliw.
Competition: Cystadleuaeth.
Competitive: Cystadleuol.
Competitor: Cystadleuydd.
Completed: Wedi'i (c/g/ch)wblhau.
Concentrate: Cryfhau.
To concentrate: Canolbwyntio.
Concentration: Canolbwytiad.
Continue: Parhau.
To continue: Parhau.
Cool: Oer.
To cool down: Oeri.
Corner: Troad.
Course: Cwrs.
Cramp: Cramp.
Cross: Croes.
To cross: Croesi.
Cross way: Croesffordd.
Cross country: Traws gwlad.
Cross training: Trawshyfforddi.
Crowd: Torf.
Crowded: Dan sang.
Cry: Llef.
To cry: Wylo/llefain/crio.
Curve: Tro.
To curve: Troi.
Cup: Cwpan.
Dark: Tywyll.
Defeat: Curo/baeddu.
Dehydration: Diffyg dwr.
Descent: Disgyn.
Determination: Penderfyniad.
Diet: Deiat.
Difficult: Anodd.
Digest (to): Treulio.
Dislocation: Rhoi allan o le.
Distance: Pellter.
Division: Adran.
Dizzy: Penysgafn.
DNF (Did not finish): NO (Ni orffennodd).
DNS (Does not start): NCh (Ni chychwynnodd).
Doctor: Meddyg.
Downhill: i lawr.
Draft (to): Drafftio.
Dress: Gwisg.
To dress: Gwisgo.
Dressing room: Ystafell Newid.
Drink: Diod.
To drink: Yfed.
Dry: Sych.
To get dry: Sychu.
Easy: Hawdd.
End: Diwedd.
Dead end: Ffordd gau/ceuffordd.
Endurance: Dyfalbarhad.
Energy: Nerth.
Energy drink: Diod atgyfnerthu.
Entry: Mynediad.
Entry form: Ffurflen gais.
Entry fee: Ffi.
Exhaustion: Lludded.
Exhausted: Lluddedig/wedi llwyr ymladd.
Error: Camgymeriad.
Faint: Penwan/ysgafn [light].
To faint: Llewygu.
Fall: Cwymp.
To fall down: Syrthio/cwympo.
To fall behind: Syrthio'n ol.
To fall apart: Syrthio'n ddarnau.
False: Gau/anwir/cam.
False start: Camgychwyn.
Far: Pell.
Fast: Cyflym.
Fastest: (Y) c/gyflymaf/cyntaf.
Fatigue: Blinder.
Favorite: Hoff/ffefryn.
Favored: Hoff.
Fee: Ffi.
Field: Maes.
Finger: Bys.
Finish: Gorffen.
Finished: Wedi gorffen.
Finish line: Llinell orffen.
First: Cyntaf.
Fit: Ffit.
To fit: Ffitio.
Flat: Wastad/fflat.
Fog: Niwl.
Follow (to): Dilyn (hyd/tuag at).
Food: Bwyd.
Foot: Troed/troedfedd [a foot in length].
Feet: Traed/troedfeddi [feet in length].
Footprint: Ol troed.
Forest: Coedwig/Fforest.
Fruit: Ffrwythau.
Gap: Bwlch.
Glory: Gogoniant.
Go!: Ymlaen!
To go: Mynd.
Goal: Nod/amcan.
Half: Hanner.
Half marathon (km 21,097): Hanner marathon.
Happy: Hapus/dedwydd/llon.
Hard: Caled.
Hat: Het.
Baseball hat: Het pel-fas.
Head: Pen.
Headband: Penrwymyn.
Health: Iechyd.
Heel: Sawdl.
Help: Help/cymorth.
High: Uchel.
Hill: Rhiw/allt/bryn/llethr.
Hip: Hip.
Hit: Ergyd.
To hit the wall: Bwrw'r wal.
Hot: Poeth.
Hurt (to): Brifo.
To get hurt: Cael anaf.
Ice: Rhew/ia.
Ice cube: Ciwbyn rhew/ia.
Jet lag: Lludded jet.
Jogging: Lloncian.
Jogger: Llonciwr(aig).
To jog: Lloncian.
Joint: Cymal.
Jump: Naid.
To jump: Neidio.
To jump the gun: Achub y blaen ar.
Kick: Cicio.
Kick of energy: Cic egni.
Kilometer (km): Cilomedr.
Knee: Penglin.
Lack: Diffyg.
Lake: Llyn.
Lap: Cylch.
Last: (Yr) olaf.
Leader: Arweinydd/y cyntaf.
To lead: Arwain.
Left: Ar ol [left over], chwith [left hand side].
Lemon: Lemwn.
Length: Hyd.
Light: Golau/ysgafn [light in weight].
Light weight: Ysgafn.
Light colored: Golau.
Limit: Pen [end], cyfyngiad [restriction].
List of result: Rhestr (o) ganlyniadau.
Long distance: Pellter hir.
Lose: Colli.
Lost: Coll/Ar goll/colledig.
To loose: Rhyddhau [loosen].
Map: Map.
Marathon: Marathon.
Market: Marchnad.
Massage: Masaj.
To massage: Rhoi masaj i.
Masters: Meistri.
Maximum: Uchafswm/mwyaf.
Medal: Medal.
Gold medal: Medal aur.
Silver medal: Medal arian.
Bronze medal: Medal efydd.
Medicine: Ffisyg/Moddion.
Man: Gwr/dyn.
Men: Gwyr/dynion.
Meter: Mesurydd [measurer], metr [metre in length].
Mid: Canol/hanner.
Mid course: yng nghanol y cwrs.
Middle distance run: Rhedfa bellter canolig.
Mile (km 1,609): Milltir.
Mind: Meddwl.
To lose one's mind: Colli pwyll.
Mistake: Camgymeriad/camsyniad.
Mountain: Mynydd.
Multicolored: pob lliw/amryliw.
Muscle: Cyhyryn.
Nausea: Cyfog.
Neck: Gwddwg.
Need: Angen.
To need: Angen.
Nervous: Nerfus/pryderus.
Nerves: Nerfau.
Night: Nos.
Non competitive: yn ddi-gystadleuol.
Number: Rhif/nifer.
Objective: Nod/amcan/gwrthrychol [without prejudice].
Observer: Sylwebydd.
Obsession: Obsesiwn.
Onlooker: Sylwebydd.
On your mark: Ar y marc.
Open: Agored.
To open: Agor.
Opposition: Gwrthwynebyddion.
Order (of arrival): Trefn (cyrraedd).
Organization: Trefn/trefniant/trefniadau.
To organize: Trefn.
Out of breath: Allan o wynt.
Overtake (to): Pasio/goddiweddyd.
Oxygen debt: Dyled ocsigen.
Pace: Cyflymdra.
Pacer: Rheolydd cyflymdra.
Pack: Praidd.
Pain: Poen.
Participant: Cystadleuydd/un sy'n cymryd rhan.
To participate: Cymryd rhan.
Party: Parti, plaid [group of like-minded people].
Pasta party: Parti pasta.
Pass: Bwlch [mountain pass], tocyn [ticket].
To pass: Pasio/goddiweddyd.
Path: Llwybr.
Paved: Wedi'i p/ph/bafio.
Pedestrian: Cerddwr(aig).
Performance: Perfformiad/perfformans.
Perspiration: Chwys.
Physical: Corfforol.
Pin: Pin.
Place: Lle/lleoliad/man.
To place: Rhoi/lleoli.
Plaque: Plac.
Pot hole: Twll.
P.R. (personal record): R.P. (Record Personol).
Prepare (to): Darparu.
Prize: Gwobr.
Promotion: Dyrchafiad/Hyrwyddiad [advertising promotion].
To promote: Dyrchafu/Hybu [to advertise].
Protein: Protin.
Psychological: Seicolegol.
Public: Cyhoedd [noun], cyhoeddus [adjective].
Publicity: Cyhoeddusrwydd.
Puddle: Pwll dwr.
Push (to): Gwthio/hybu [to promote].
Qualify (to): Cyrraedd safon/mynd trwodd.
Qualifying round: Rownd rhagbrofol.
Quick: Cyflym.
Quit (to): Rhoi'r gorau (i).
Rabbit: Newydd ddyfodyn [newbie], cwningen [the animal].
Race: Ras/tras [ancestry], dynoliaeth [human race].
To race: Rasio.
Racer: Rasiwr(aig).
Rain: Glaw.
Record: Record.
Recover (to): Adfer.
Refreshment: Lluniaeth.
Refreshing: Atgyfnerthol.
Registration: Cofrestru.
To register: Cofrestru.
Registration fee: Tal cofrestru.
Rehydration: Cael dwr yn ol.
Relay: Cyfnewid.
To relay: Cyfnewid.
Repeats: Gweithiau.
Resistance: Gwrthwynebiad.
Rest: Saib/seibiant.
Rest stop: Arhosfan seibiant.
Result: Canlyniad.
Retire (to): ymddeol/syrthio allan.
Ribbon: Rhuban.
Right: Cywir [correct], De [right hand side].
Road: Ffordd/heol/lon.
Route: Ffordd.
Run: Rhedfa [noun], Rhedeg [verb].
Runner: Rhedwr(aig).
Runner's high: Gorfoledd y rhedwr(aig).
To run: Rhedeg.
Salt: Halen.
Scenic: Gyda golygfeydd da.
Schedule (training): Trefn.
Score: Sgor.
Second: Eiliad [1/60 minute], ail [ordinal].
Separate: Ar wahan.
To separate: Gwahanu.
Shape: Siap/llun.
Sharp (pain): (Poen) pigog.
Shirt: Crys.
T-shirt: Crys-T.
Shoes: Esgidiau.
Shoelace: Carrai.
Short: Byr.
Shorts: Trowsus byrion.
Shoulders: Ysgwyddau.
Sidewalk: Pafin.
Slow: Araf.
To slow down: Arafu.
Snow: Eira [noun], bwrw eira [verb].
Socks: Hosanau.
Sole of foot: Gwadn y troed.
Sore: Llidiog.
Spectator: Edrychwr.
Speed: Cyflymdra.
To speed up: Cyflymu.
Speed session: Sesiwn cyflymdra.
Split time: Amser y rhan.
Sponsor: Hyrwyddwr(aig).
To sponsor: Hyrwyddo.
Sprain: Tro [noun], troi [verb].
Stadium: Stadiwm.
Stagger start: Cychwyn ar wahanol amseroedd, neu o wahanol lefydd.
Start: Cychwyn.
To start: Cychwyn.
Starting line: Llinell gychwyn.
Starting block: Bloc cychwyn.
Starter: Cychwynydd.
Starter's gun: Gwn y cychwynydd.
False start: Cychwyn cam.
Steep: Serth.
Steroids: Steroidau.
Stomach: Bol/stumog.
Stop (to): Stopio/aros.
Stoplight: Golau stopio.
Straight: Syth.
Stranger: Dieithryn.
Street: Styd/heol/lon.
Strength: Nerth.
Strenuous: Caled.
Stress: Stres/pwysau.
Stretching: Ymestyn.
To stretch: Ymestyn.
Stride: Cam [noun], brasgamu [verb].
Sugar: Siwgwr.
Sun: Haul.
Sweat: Chwys.
To sweat: Chwysu.
Sweat suits: Gwisg chwys.
Sweats: Chwysau.
Tea: Te.
Team: Tim.
Tempo run: Rhedfa dempo.
Tendon: Llinyn.
Tense: Tyn.
To tense: Tynhau.
Tension: Tyndra.
Tight: Tyn.
Thigh: Mordwydd.
Thin: Tenau.
Third: Traean [1/3], trydydd [ordinal].
Throb (to): Curo.
Time: Amser.
Timer: amserydd.
Timekeeper: Amserwr(aig).
Time trial: Prawf amser.
Tired: wedi blino/blinedig/lluddedig.
Toe: Bys troed.
Big toe: Bys bawd y troed.
Tongue: Tafod.
Towel: Tywel.
Town: Tref.
Training: Hyfforddiant.
Trainer: Hyfforddwr.
Track: Cylch rhedeg.
Tread: Cynllun gwadn.
Triathlon: Triathlon.
Trophy: Gwobr.
Trouble: Trybini/trafferth/trwbl.
Trouble free: di-drafferth.
Turn (to): Troi (at).
Unpaved: Heb bafin.
Uphill: ar i fyny.
Valley: Cwm/dyffryn.
Vaseline: Fasalin.
Veteran: Aeddfed/hyn [adjective], person aeddfed [noun].
Victory: Buddugoliaeth.
View: Golygfa [scenery], safbwynt [standpoint].
Vitamin: Fitamin.
Walk: Cerdded [verb], taith gerdded [noun].
Warm: Cynnes.
To warm up: Cynhesu.
Watch out!: Ylwch!/Sgwlwch!
To watch: Gwilio.
Watch: Wats/oriawr.
Water: Dwr.
Water closet: Ty bach/lle chwech.
W.C.: Ty bach.
Weak: Gwan.
Weather: Tywydd.
Weightlifting: Codi pwysau.
Wet: Gwlyb.
Winner: Enillydd.
To win: Enill.
Woods: Coedwigoedd.
Woman: Menyw/merch/dynes.
Women: Menywod/merched/gennod.
Worn out: Wedi treulio [worn thin], wedi blino [tired].
Year: Blwyddyn.
