degül, dejil

is not

Comments: Ramstedt 1924 derived it from *tüke- `be exhausted' (see under *t`ukì), i.e. "being exhausted, having come to an end" = "is not". The semantic derivation seems quite probable, but PT *degül is phonetically not derivable from *tüke-; it appears rather to be derived from an otherwise unattested PT *degü- < PA *tagi, but with the same semantic shift. There is yet another possibility available
Russian meaning: нет, не
Karakhanid: tegül (MK Oghuz)
Turkish: degül, dejil
Tatar: tügil
Middle Turkic: degül (Pav. C.)
Azerbaidzhan: dejil
Turkmen: dǟl
Kirghiz: tügül
Kazakh: tügil
Noghai: tuwɨl
Bashkir: tügil
Karaim: duguĺ
Karakalpak: tüwe
Kumyk: tügül