Comments:Poppe 38, АПиПЯЯ 51, 286, KW 276. A Mong.-Tung. isogloss. A probable reflex in Jpn. is OJ num(j)er- 'be slippery' - with the meaning influenced by *nàmià 'slippery' (see *ni̯ùmà). The roots *ni̯ombu and *ni̯uma generally tend to influence each other.