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Ubĭi, ōrum, m., a Germanic people, who in Cœsar’s time occupied the territory on the east bank of the Rhine, near the mod. Cologne, but were transferred to the left bank of the Rhine by Agrippa, B. C. 39, Caes. B. G. 1, 54; 4, 3; 4, 16; 6, 9; Tac. G. 28; id. A. 1, 31; 1, 36: oppidum Ubiorum, their chief city, id. ib. 1, 39; 1, 57.
Hence, Ubĭus, a, um, adj., Ubian, of the Ubii: mulier Ubia, Tac. H. 5, 22.