Proto-West-Caucasian: *ḳ́ač̣ʷǝ
Meaning: short
Abkhaz: a-ḳ́áč̣
Adyghe: č̣́ač̣́ǝ
Kabardian: č̣aṣ́
Comments: PAK *ḳač̣́ǝ́. Identifying *ḳa as 'tail' and treating the PAK form as 'empty-tailed' (thus in Shagirov 2, 134) is obviously a folk etymology. The Abkh. word may be, but not necessarily is, an AK loanword (phonetic correspondences are quite regular here).