The reconstruction of the root-final stop faces some contention with most older sources preferring the labiovelar*kʷ,[1][2] while other sources question[3][4] or outright reject the labiovelar[5][6] in favor of the plain velar*k.
The evidence in favor of the labiovelar consists primarily of theHittite𒉿𒀜𒆪𒍖𒍣(wa-at-ku-uz-zi/watkuzi/,“to jump (out of), to flee”), which must come from an athematic stem ending in*kʷ and which may come from auniverbation of*wé-tkʷ-ti. Kloekhorst mentions, however, that this could also be a root*wetkʷ- comparable to stems such as*h₂edʰǵʰ- or*tetḱ-.[7]
Also, there is the proposal thatProto-Germanic*þewaz(“servant”) came from earlier*þehwaz from*tekʷós. While Kroonen prefers the Germanic-only root*tew-,[4] the EIEC ascribe this and other such forms as*-w- extensions of the root.[5] If theSanskritतकु(táku,“running along”) represents a*-u- stem adjective*tékʷ-u-s ~ *tkʷ-éw-s, this could explain the appearance of this extension.
In favor of the plain velar is theTocharian Bcake(“river”) fromProto-Tocharian*cäke, which Adams derived from*ték-es- or*ték-ont- meaning “that which flows.”[6]
Ambiguously, the general absence ofProto-Brythonic*-b- in the descendants ofProto-Celtic*tek(ʷ)eti (Middle Bretontechet,Cornishtêgh,Middle Welshtechu) points to the velar being plain. Matasović, however, gives the explanation that the Brythonic*-x- was derived from the Celtic*-s- subjunctive:*tekʷs- > Brythonic*tex-, and that the labiovelar does surface in the formOld Welshny-debit(imperfect impersonal relative) found inAneirin.[8]
↑6.06.16.2Adams, Douglas Q. (2013), “cake”, inA Dictionary of Tocharian B: Revised and Greatly Enlarged (Leiden Studies in Indo-European;10), Amsterdam, New York: Rodopi,→ISBN,page267
↑7.07.1Kloekhorst, Alwin (2008), “u̯atku-ᶻⁱ”, inEtymological Dictionary of the Hittite Inherited Lexicon (Leiden Indo-European Etymological Dictionary Series; 5), Leiden, Boston: Brill,→ISBN,pages989-990
