Comment: The Arch. form can belong both here and to the PL *ʔaχär- 'sleep, lie' q.v. The original meaning of PL *ʔaqɨ- must have been 'to fall, to become spilled, scattered', cf. Ag. l-aqa-s (Bursh. aqi-s) 'to scatter, spill, get scattered' (cf. also in Tab. without the d- preverb aq- 'to fall'), Arch. c-a=χa- 'to fall; to throw' (with an expressive preverb) and possibly also Lezg. al-aq- 'to stick, adhere', Ag. ʕ-aq- (Bursh. ʕ-aqi-) 'to mix'.
Cf. also Tab. al-a=q-, Düb. h-a=q-, Ag. ʕat:-aq- 'to meet, encounter' (*"to fall upon") - which may have obtained its meaning due to the influence of PL *ʔiqɨ- 'to find' (q.v.), or may, in fact, provide a link between these two roots (stems): see PEC *=iq_wV.