Proto-Mongolic *kab- (“narrow”) perhaps suffixed with -ца- (-ca-) + -л (-l).
Compare with Buryat хабсал (xabsal, “cliff, gorge”).
хавцал • (xavcal) (Mongolian spelling ᠬᠠᠪᠴᠠᠯ (qabčal)); (regular declension)