Comment: Cf. also Tab. Düb. jac, Ag. Bursh. jacʷ, Fit. wic, Burk. wec. The original medial nasal *-m- is preserved (as -n- before a sibilant) only in Arch. All other languages have lost it, but Agul has preserved the compensatory labialisation (Proto-Ag. *jawc; in Rich. bec regularly < *wec, cf. the forms in other dialects). All correspondences are regular (including the fronting *a > e in Rich. and Burk. before a hissing affricate, and the development *ja- > *ji- in a closed syllable in Tab.).
The obl. base can be reconstructed as *jamca- (cf. Rut. jasa-, Tsakh. jaca-, Arch. erg. ansa); 3d class in all class-distinguishing languages.