I've done extensive research; each word in this list has its source in at least one of the books in the literature list below. But there still can be some misinterpretations in this list.

Tips:
• Pronounce `c` mostly as `k`.
• `-` means you must add another word.
• words with (NL) are possible originally ancient `Dutch`.
• words with (GB) and (BB) are `Islandceltic`/`Belgian` (because of the flight of Belgians to England)
• words with (GL) are probably Gallo-Latin / Gallo-Roman
• words with (#) are (part of) geographic names.
• words with (R?) are possibly just Latin.
• words with (L) are possibly pre-gaulish (=Ligurian).
• words with (+) are also names of gods/ religious comprehensions.
• words with (m) are names of chronology and other information according to the `moon-calendar` from Coligny,France.
• words with (pC) are possibly proto- (=reconstructed) Celtic, written phonetically
• pl=plural, eg=for example
• / and , =spelling unsure, perhaps depending on dialect, case or place in the text.
• the "U" can also indicate a "V" and vice versa.
• the ^notes refer to a source in the literature list.

R.

raithin = fortification
raon = field
rap = wet grass-land^AS
ratin = fortress, residence, a rampart ^{HL, JM}
ratis = fern ^PS
raud = red
reda = 4 wheeled wagon, cart ^{HL, JM}
regu = I straighten
rene = rebirth (#) ^IW
rextu(s) = law, order, arrangement ^{HL, JM}
rhena = Rhine (#) ^IW
rica = lane of seed
rigion = kingdom
rigyo- = realm ?, rich ?, powerful ? (pC) (suffixed form) ^HM
ritu = passage
ritum = wheel
ritus = runner
riuros = "frost time" (month) (m)^RW
rix, rigo(s) = king ^{HL, JM}
-rix, -rex, -reix = king, chief ^PS
ro- = very
ro- = (pC) (intensive prefix) ^HM
rocca = rook
rowero = sufficiency (pC) ^HM

S.

saf = swamp^AS
sagus/m (pl: sagi) = woolen cloak that only covers the back (not the shoulders) or "long tunic"
saliva = spittle
salmo = salmon, "the leaping fish"  ^HM
samain = a certain feast
samon/ios = summertime, summery-end or seed-time (month)(m)^RW
-samus (superlative suffix) = -est (superlative suffix) ^{HL, JM}
sapo = soap hair colourer
sasiam = rye
sedlon = see, place
sego- = strength ^PS
Segodunum = Wurzburg, D? (#) ^{BC, JM}
segomaros = the name of the son of villo/nos 1st/2nd century BC. at Vaucluse (Nimes,France?)
sel = swamp (#)
selua = possession ^{HL, JM}
seno- = old
seno(s) = old ^{HL, JM}
senomagus = the old plain (#)
sexta = seven^JM
sextametos = seventh ^{PS, JM}
sigovesus = `he who can conquer`, the name of an important leader 400 BC
simiuisonnos = "semi-springtime", month (m)^RW
Singidunum = Beograd, Serbia (#) ^{BC, JM}
slogi = people
slogi, slugi = servant, slave ^{HL, JM}
smer = fat, grease ^{HL, JM}
so-sendha = that yonder ^{HL, JM}
sosin = that, this ^{HL, JM}
sosio = this
stannum = tin
sto- = standing (pC) ^HM
strato-, srato-, wide river valley (pC) ^HM
su- = beautiful, good
suadu(s) = pleasant ^{HL, JM}
sub = with
sucarus = well-loved ^PS
sucellus = good beater, hammergod (+)
suex = six^JM
suexos = sixth^JM
suiorebe = to sisters ^PS
sukko- = swine, snout of a swine, plowshare (pC) (expressive form)^HM
sunartiu = with the good strength

T.

talo/s = brow, ground
tamisium = sieve
taran- = thunder-
taran, taranis = god of the thunder, thunderer (+) ^PS
taratrum = auger ^PS
tarb/h = bull (GB)
tarbh feis = bull-festival (GB)
taringa, tarinca = spike, point, nail (GL) ^PS
taruos = bull ^{HL, JM}
tarvos = bull
tarvostrigaranus = bull-god with 3 cranes (+)
tazgo- = badger (pC) (totemic name) ^HM
taxi- = soft
tegia = hut
teuoxtoni(o)n = of gods and men ^PS
teutha, touta, tota, teuto = tribe, settlement, people ^{PS, HL, JM}
teut(h)ates, toutates = protector of the tribe (+)
Teutoburgium (Hungary) (#) ^{BC, JM}
thigernum = - lord (GL) ^PS
thigernum = house ^{HL, JM}
thirona, sirona = star, also the name of a goddess (+) ^{HL, JM}
tinca = tench
Tincommios = the name of the son of Commios (BB)
to = to, in, from ^{HL, JM}
Tolosa = Toulouse, F (#) ^{HL, JM}
torko, torka = torque, neck-ring ^OS
tout(o)- = people
toutiorix = ruler of the tribe(+) (=other name for teutates)
tragus = foot ^{HL, JM}
treide = foot? ^PS
tri = three^JM
Tricasses = Troyes, F (#) ^{BC, JM}
tricontis = period of 30 days (m)
trinanto = 3 valleys (#)

The triquetrum image was used as a typical decoration by Gauls

U.

ue, ve = under ^{HL, JM}
uediju = I beseech
uediiumi = I pray ^PS
uer, ver = over ^{HL, JM}
Uernodubrum, Vernodubrum = alder-water ^{BC, JM}
uertragus, vertragus = swift-footed dog ^{HL, JM}
uindo(s), vindo(s) = white ^{HL, JM}
uinom = wine
uirus, virus = true ^{HL, JM}
uisu(s), visu(s), uesus, vesus = worthy ^{HL, JM}
uta = and ^AC
uxello = noble
Uxellodunum (F) (#) ^{BC, JM}
uxello(s) = high ^{HL, JM}
Uxisame (F-Brittany) (#) ^{BC, JM}

V.

valo, ualo = leader ^PS
vasso = vassal, servant ^OS
(-)vec- = fight? ^PS
velleda = female soothsayer
velo = I see
ver-, vero-, viro- = over, super, leader ^PS
vercingetorix = name of a chief king (`who marches against the foe`?), see "cingetos"
vercobreto, vergobretus = burgomaster
vercobreto (dual) = (two) magistrates ^{HL, JM}
(para-) veredus = post-horse ^PS
vergo = judgement
Vergobretes = "executioners of the law"
vergobretus, uergobretus = chief magistrate, with power over life and death ^{HL, JM}
verica = name of the son of commios (BB)
vernos = alder
vernomagus = alder field / old field
Verona = Verona, I (#) (maybe pronounced uerona?) ^{HL, JM}
verritus = `super-runner`, name of a king of the Frisii 1st century BC.
verrix = super-king
vertragos / us = fast hunting dog, greyhound (imported by the Romans?) ^PS
vesus = good
vices = "those who fight" (pC) ^HM
vid = to see
vids = seeing
vidu = wood, forest, tree (#)
vindo- = white ^PS
Vindobona = Vienna, Vindonissa (CH) (#)^{BC, JM}
viria = wristband (bracelet?)
viriae = bracelets (pC) ^HM
viriola/e = belt
Visurix= (name. probably Teutonic)
vlatos = chief, prince
vo- = under
Vulcanos = god (of fire?) (+)

W.

was = mud ^AS
wasso- = "one who stand under" (pC) ^HM
wero- = true ? (pC) ^HM
wik = to fight, conquer (pC) ^HM
wo- = under (pC) ^HM

Y.

yowanko = gallowglass (pC) ^HM

LITERATURE SOURCES:

• M.Ball, J.Fife, The Celtic Languages.
• Bernardino Biondelli, Saggio sui dialetti Gallo-italici.
• P.H. Billy, Thesaurus Linguae Gallicae. 1993.
• Bompiani, The Celts. 1991.
• J. Boosten, Godsdienst der Kelten. 1950.
• H. Brunsting, Archeologie en historie. 1973.
• ^ACAedeen Cremin, The Celts in Europe.
• ^BCB. Cunliffe, The Celtic World. 1979.
• L.A. Curchin, (internet information). 1997.
• X. Delamarre, Le vocabulaire indo-européen.
• Dizionario Garzanti della Lingua Italiana.
• Dizionario LeMonnier della Lingua Italiana.
• M. Dillon, The Celtic realms. 1974.
• G. Dottin, La langue gauloise. 1920.
• D. Durante, Dizionario etimologico Veneto-Italiano.
• P.M. Duval, Die Kelten. 1978.
• P.M. Duval (Dir.), Recueil des inscriptions gauloises. 1985.
• D. E. Evans, Gaulish Personal Names. 1967.
• ^HMHoughton Mifflin Company, The American Heritage College Dictionary, 3rd edition. 1993.
• G. Herm, De Kelten. 1975 and 1979.
• A. Holder, Altceltischer Sprachschatz (fundamental). 1896-1913.
• H. Hubert, The rise of the Celts. 1934.
• F. Jung, De Germanen. 1978.
• S. James, Ontdek de wereld van de Kelten. 1996.
• E. Jung, De Germanen. 1978.
• C. Kalondan, De wijsheid der druiden. 1990.
• P.Y. Lambert, La langue gauloise. 1994.
• ^HLH. Lewis and H. Pedersen. A Concise Comparative Celtic Grammar. 1974.
• A.MacBain, An etymological dictionary of the Gaelic language.
• M.Malherbe, Les languages de l'humanité.
• R. Marichal, Les graffites de La Graufesenque. 1988.
• ^JMJ. Mascitelli, (correspondence 1999, 2000)
• W. Meid : 'Gaulish Inscriptions. 1994.
• Meid W. & P. Anreiter (Herausgeb.), Die grösseren altkeltischen Sprachdenkmäler. 1996.
• Museé de Moyen-age "Cluny", Paris. 1997.
• F.Nicoli, Grammatica milanese.
• ^ASA.P.G. Spamer, Deurne en de Peel in de brons- en ijzertijd. 1998.
• Savinian, Grammaire Provençale.
• K.H. Schmidt, Die Komposition in gallischen Personennamen. 1957.
• P. Schrijver, lecture "Celts and Teutons in the Netherlands". 1997.
• ^PS P. Schrijver, Studies in British Celtic historical phonology, 1995.
• ^OS O. Szemerényi, An den Quellen des lateinischen Wortschatzes, 1989
• Tacitus, Germania. 98 A.D.
• L. Toorians, Scarabee.Dec. 1997.
• L. Toorians, Spiegel Historiael. 1993.
• ^LTL. Toorians, lecture 1999: "The 'P' doesn't exist in Celtic"
• V. Veen, Etymologic Dictionary.
• De Vooys, Geschiedenis van de Nederlandse taal. 1970
• J. Watmough, 'The Dialects of Ancient Gaul'. 1970.
• ^IW I. Wilkens, Where Troy once stood. 1990
• ^RW About Coligny's calendar, by "Myrddyn"
• About Coligny's calendar, by Ray White

I hereby wish to thank Andrea De Vecchi, mr. J. Mascitelli and mr. X. Delamarre for adding many Gaulish words to this list.