Proto-CChadic: *ʔa(m)b-
Meaning: 'elephant/hippopotamus'
Gisiga: ʔabu 'hippopotamus' Bl. Eleph., 202; together with ngabu called "the later loans...from Ful", which is obviously so in the latter case (Ful ngabu, pl. gabi), but hardly so in case of ʔabu.
Buduma=Yedina: ambu 'elephant' Bl. Eleph. 198 apud Sölken; comp. to Log. nevi, Makeri árfu, etc.; Ngala ambu (also amwe, anwe) Porkh., 34
Notes: Both Blaz. Eleph., 198 and Porkh., 34 unite all Kotoko forms reconstructing *ʔarbu/i (Blazek, ibid.) and *Vr(V)pV (Porkh. ibid.; irregularity of the reflexes of *p is is explained by the "combinatorial influence of the sonant", which is far from convincing). One cannot exclude two (or even three) different roots