A Palestinian amora of the fourth generation, disciple of R. Ḥanina b. Pappi, and contemporary of R. Hezekiah. It is surmised that his patronymic Abimi was changed into Ukmi or Ikkuma, that is, "the Dark," because his memory was not retentive enough to guard him against the misquoting of traditions (Yer. Ber. 9:14a; Yer. Ta'anit, 3:64b; 'Er. 9b, 12a; Beẓah, 26b).