Комментарии:In Turkic one has to suppose vowel assimilation (*Küĺül < *Keĺül), and in Mong. - a regular r/l metathesis ( < *keler-ǯegene). Cf. a number of similar roots, with a possibility of contaminations: see *keru, *k`i̯ū́ĺa, *ki̯ùti, *k`ela.
