Notes: The historical unity of the Nakh and Av.-And. forms is quite obvious, so the word goes back at least to PEC. Other forms are less secure: we could find the Tsakh. and Khin. forms only in Khaidakov's somewhat unreliable word-list, and the Abkh. form is isolated within WC.
Outside NC the same word is attested in Megr. (beha, see above) and Arm. bah. The Armenian word has no reliable IE etymology (its deduction from IE *bhr_ti- 'edge' is both phonetically and semantically quite dubious, see Walde-Pokorny 2, 159) and most probably has a Caucasian source.