Words for quick, fast, crazy, lively, ready and related things in Celtic languages.

Words marked with a * are reconstructions.

Middle Irish (Gaoidhealg)	tap = sudden tapad = suddenness, haste, quickness, bravery tapaid = quick, swift, active
Irish (Gaeilge)	tapa [ˈt̪ˠapˠə] = quick(ness), ready, active, speed, vigour tapaigean = sudden start, spring, jump, mishap tapaigh = to quicken, grasp quickly tapaíoch = quick, active, alert person tapaíocht = quickness, activeness, alertness tapóg = tendency to jump, nerviness, sudden impulse tapógach = jumpy, nervy, impulsive
Scottish Gaelic (Gàidhlig)	tapadh [tahbəɣ] = cleverness, smartness, thanks, alertness, feat, achievement tapadh leat/leibh = thank you tapaidh [tahbɪ] = clever, smart, brave, heroic, active, vigorous all-tapadh = mishap, accident, misfortune
Manx (Gaelg)	tappee = fast, hasty, quick, rapid, speedy, swift tappeeid= quickness, rapidity, speed tappeeys = quickness, rapidity, speed, nimbleness

Etymology: uncertain

Old Irish (Goídelc)	opunn = fast, prompt, quick
Middle Irish (Gaoidhealg)	opunn, obunn, opund, topund = quick, swift, prompt, hasty, precipitate
Irish (Gaeilge)	tobann [ˈt̪ˠɔbˠən̪ˠ] =sudden, unexpected, hasty, impulsive, quick-tempered
Scottish Gaelic (Gàidhlig)	obann [obən̪ˠ] = sudden, unexpected gu h-obann = suddenly

Etymology: uncertain

Old Irish (Goídelc)	ellam, ollam, ullam = quick, ready, soon, speedy
Middle Irish (Gaoidhealg)	ellam, ollam, ullam = quick, prompt, speedy, soon, readily, ready, prepared, finished, complete ellma = speed, rapidity, promptness, speedily, soon, prompty, soon enough, ready, prepared ellmaigid = to prepare, make ready
Irish (Gaeilge)	ullamh [ˈɔl̪ˠəvˠ/ˈʊl̪ˠuː] = ready, willing, prompt, prepared, predisposed inclined, finished ullmhacht = readiness, preparedness ullmhaigh = to make ready, prepare ullmhaitheach = preparative ullmhaitheoir = preparer ullmhú = preparation ullmhúchán = preparative, preparation
Scottish Gaelic (Gàidhlig)	ullamh [ul̪ˠəv] = done, finished, ready, prepared, mature, handy, prone to ullamhachadh [ul̪ˠəvəxəɣ] = preparing, getting ready, preparation, arranging, arrangement, providing, provision ullamhachd [ul̪ˠəvəxg] = readiness, preparedness, proneness, aptitude, aptness
Manx (Gaelg)	ullee = conversant, operational, prepared, ready

Etymology: from Old Irish ar (for, on), fo- (under, sub-) and lám (arm, hand) [source].

Old Irish (Goídelc)	mer = crazy meraige = crazy person, fool
Middle Irish (Gaoidhealg)	mer = demented, crazy, wild, rash meraige = a muddle-headed or scatter-brained person; aberration, derangement
Irish (Gaeilge)	mear [mʲaɾˠ] = quick, fast, nimble, lively, spirited; precipitate, hasty, rash; quick-tempered, fiery; mad, crazy; furious, raging, angry mearadh = madness, insanity, craze, craving mearaí = crazed person, distracted, bewildered, person, craziness, distraction, bewilderment mearaigh = to derange, distract, bewilder, confuse, to become distracted mearaitheoir = distracter, bewilderer, infuriating person.
Scottish Gaelic (Gàidhlig)	mear [mɛr] = merry, joyful, frisky, lively mearachas [mɛrəxəs] = mirth, merriment mearachd [mɛrəxg] = merriness mearaiche = droll / merry person
Manx (Gaelg)	merre [mɛr] = frenzy
Welsh (Cymraeg)	miri = merry, gay, fun, merriment, mirth, tumult, fuss, bother, predicament miriman = fool, clown, wild and unruly person miriol = merry, gay

Etymology: possibly from English merry, or Middle English mery (happy, joyful, pleased), from Old English myrġe (pleasant, attractive, enjoyable), from Proto-West Germanic *murgī (short, slow, leisurely), from Proto-Germanic *murgijaz/*murguz (short, brief slow, leisurely), from Proto-Indo-European *mréǵʰus (short, brief) [source].

Proto-Celtic	*lim-ā- = to sharpen, polish
Old Irish (Goídelc)	límaid = to polish, sharpen
Middle Irish (Gaoidhealg)	límaid, límad = sharpens, grinds, polishes límtha = sharpened, burnished, keen, polished, fluent límugud = act of sharpening
Irish (Gaeilge)	líomh [mʲaɾˠ] = to grind, sharpen, file, smooth, polish, erode, destroy líomhadh = to grind, polish, erosion, destruction líomhadóir = grinder, filer, polisher líomhán = file
Scottish Gaelic (Gàidhlig)	lìomh [l̪ʲiəv] = polish, gloss, burnish, refinement
Manx (Gaelg)	shleeu = to grind, sharpen, whet, grinding, sharpening shleeuan = file shleeuee = grinder
Middle Welsh (Kymraec)	llim, llym, lem = sharp, pointed, keen, harsh, shill, quick, swift lllymu = to whet, file, sharpen llymaidd = sharp, keen, piercing, harsh, severe, eager, ardent llymder = sharpness, keenness, harshness, severity cyflym, kyflym = quick, swift, speedy, brisk, quick-witted, intelligent, ready, clever, sharp, keen, acute kymlymder, cyflymdra = swiftness, quickness, rapidity
Welsh (Cymraeg)	llym [ɬɨ̞m/ɬɪm] = sharp, pointed, keen, harsh, shill, quick, swift llymaf, llymu = to whet, file, sharpen, speak severly llymaidd = sharp, keen, piercing, harsh, severe, eager, ardent llymder = sharpness, keenness, harshness, severity cyflym = quick, swift, speedy, brisk, quick-witted, intelligent, ready, clever, sharp, keen, acut cyflymaf, cyflymu = to quicken, accelerate, hasten, expedite cyflymder = swiftness, quickness, rapidity
Middle Cornish (Cernewec)	lemma, leamn, lemen, lemmen, lemyn, lemmyn, lymmyn = to sharpen, whet
Cornish (Kernewek)	lymm, lebm = sharp, acute, keen, piercing, insightful llymma = to sharpen
Middle Breton (Brezonec)	lem, lemm = sharp, pointed, acute lemaff, lemmaff = to sharpen, make sharp lemder = acuity lemer = sharpener
Breton (Brezhoneg)	lemm = pointed, sharp, acute lemmañ, lemmiñ = to sharpen, make sharp lemmded = acuity lemmell = sharp lemmerez = sharpener lemmet = sharp(ened), keen, pointed

Etymology: probably from PIE *sley- (smooth, slick, sticky), or from Latin līma (file), from the same PIE root [source]. Words from the same roots include slime in English, and llif (saw) in Welsh [source].

Proto-Celtic	*bīwonos = ?
Middle Welsh (Kymraec)	buan= fast, swift, rapid buander = quickness, alacrity, swiftness, speed buaned, buanez = quickness, swiftness, speed
Welsh (Cymraeg)	buan [ˈbɨː.an/ˈbiː.an] = fast, swift, rapid yn fuan = soon mor fuan â phosibl = as soon as possible buanaf, buanu = to accelerate, hasten, move swiftly buander = quickness, alacrity, swiftness, speed buanedd = quickness, swiftness, speed
Cornish (Kernewek)	buan = lively, quick
Old Breton	buenion = quck, fast
Middle Breton (Brezonec)	buan = quck, fast
Breton (Brezhoneg)	buan = quick, fast buanaat = to accelerate buanaer = accelerater buanded = speed, rapidity

Etymology: probably from Proto-Celtic *biwos ((alive, living, mortal) from PIE *gʷeyh₃- (to live) [source]. Words for life and food come from the same roots, as do English words such as bioology, quick, vital, vivid and zoo [source].

Proto-Brythonic	*parọd = ready, prepared
Middle Welsh (Kymraec)	paraut, paravt, parawt = ready, prepared, arranged, quick, prompt, immediate, sudden, nimble, easy, available, convenient paroded = readiness, prepardness, willingness parotruyd, parodrwyd = readiness, willingness embaratoi, ymbarot(t)oi = to prepare (oneself), provide oneself with necessities
Welsh (Cymraeg)	parod [ˈpa(ː)rɔd] = ready, prepared, arranged, ready-made, instant (coffee, etc), quick, prompt, immediate, sudden, nimble, easy, available, convenient, absolute, downright parodaf, parodi = to make ready, prepare parodrwdd = readiness, willingness paratoi [paraˈtɔi̯] = to prepare ymbaratoi = to prepare (oneself), provide oneself with necessities
Middle Cornish (Cernewec)	parys = ready
Old Cornish	parot = prepared, ready
Middle Cornish (Cernewec)	parys = prepared, ready parusy = to make ready, prepare
Cornish (Kernewek)	parys = conventient, handy, ready pareusi, paruji = to cook, edit, make ready, prepare ombareusi, ombaruji = to get ready, prepare oneself
Middle Breton (Brezonec)	paret = cooked, boiled paredet = cooked, boiled pareiff = to boil, cook
Breton (Brezhoneg)	pared [ˈpɑː.rɛt] = cooked, boiled paredigezh = heat wave paredin, parediñ = to cook paredus = heating

Etymology: from Latin parātus ((alive, living, mortal) from PIE parō (I prepare), from PIE *perh₃-o (providing), from *perh₃- (to grant) [source].

Words from the same PIE roots include pare (to remove the outer covering or skin of something with a cutting device) in English, paràre (to adorn, protect, shield) in Italian, parar (to stop, put up, lift, raise) in Spanish [source] and words for grace and favour in Celtic languages.

Proto-Celtic	*skīto- = tired *exs-skīto- = tireless
Old Irish (Goídelc)	scíth = irksome, tired, wearisome, weary éscaid = eager, quick, willing
Middle Irish (Gaoidhealg)	scíth = weary, tired, sad, dejected éscaid, esceth, esced, esgaid = prompt, willing, alert, quick, eager, speedy, swift éscaidecht, éscaidhecht, éasgaidheacht = promptness, readiness, speed ainéscaid = slow, unhurried airéscaid = very active, nimble
Irish (Gaeilge)	scíth = tiredness, fatigue, rest scítheach = tired, weary scíthigh = to become tired, exhausted éasca = swift, nimble, free, fluent, easy, ready éascaiagh = to make easy, hurry, expedite éascaíocht = speed, expedition, nimbleness, quickness, fluency, ease, readiness, promptness
Scottish Gaelic (Gàidhlig)	sgìth [sgʲiː] = tired, weary, fatigued sgìtheachadh [sgʲiː.əxəɣ] = fatiguing, wearing, (act of) trying someone’s paticence sgìth [sgʲiː] = èasgaidh [iəsgɪ] = active, energetic, nimble, readiness to oblige èasgaidheachd = facility, nimbleness, readiness to oblige
Manx (Gaelg)	skee = fatigued, tired, weary skeeagh = tired, tiresome, wearisome, wearying easkey = rapids
Middle Welsh (Kymraec)	escud, esgud, escut, esgut = quick, swift, fleet,ready, lively, nimble, active, dexterous, diligent escudruyd, escydrwydd = quickness, swiftness, fleetness, liveliness, agility, diligence
Welsh (Cymraeg)	esgud = quick, swift, fleet,ready, lively, nimble, active, dexterous, diligent esgudrwydd = quickness, swiftness, fleetness, liveliness, agility, diligence esgutâf, esgutáu = to quicken
Cornish (Kernewek)	skwith = sleepy, tired, weary skwitha, skitha = to exhaust, tire, weary skwithans = fatigue, lassitude, tediousness, tiredness, weariness skwithhe = to tire, exhaust, weary uskis = express, fast, quick, rapid, speedy, swift uskisell = accelerator uskishe = to accelerate uskitter = velocity
Middle Breton (Brezonec)	scuyz, scuih = tired, weary, fatigue scuyzaff = to make tied
Breton (Brezhoneg)	skuizh = tied, weary, fatigue skuizhadur = lassitude skuizhañ = to make tied eskuit = agile, alert, diligent, prompt eskuited = agility, diligence, promptness

Etymology: uncertain

For other words for quick see the Celtiadur posts: Early and Soon

Sources: Wiktionary, Etymological Dictionary Of Proto Celtic, In Dúil Bélrai English – Old Irish glossary, eDIL – Electronic Dictionary of the Irish Language, Teanglann.ie, Am Faclair Beag, An etymological dictionary of the Gaelic language, Fockleyreen: Manx – English Dictionary, Online Manx Dictionary, Gaelg Corpus, Geiriadur Prifysgol Cymru, Lexicon cornu-britannicum : a dictionary of the ancient Celtic language of Cornwall, Gerlyver Kernewek, Devri : Le dictionaire diachronique du breton, Geriafurch, TermOfis