Comments:PT *bokursɨ probably < *bakursɨ (with a vowel narrowing in the first syllable of a trisyllabic word); PTM *bāgba < *bāk-ba through assimilation. Note a remarkable similarity of the Turkic and Japanese derivation. Cf. other similar roots: *p`i̯ùgV, *pŏ̀k`è, *p`ū̀ge, *p`àgò.