‖n. [ NL., fr. Gr. &unr_; terrible + &unr_;, &unr_;, horn. ] (Paleon.) A genus of large extinct Eocene mammals from Wyoming; -- called also Uintatherium. See Illustration in Appendix. [ 1913 Webster ]

☞ They were herbivorous, and remarkable for three pairs of hornlike protuberances on the skull. The males were armed with a pair of powerful canine tusks. [ 1913 Webster ]

n. a small order of primitive ungulates of the Paleocene and Eocene.
Syn. -- order Dinocerata. [ WordNet 1.5 ]