"A former genus (now included in the genus Merycoidodon) of extinct pig-sized ruminant mammals of the family Oreodontidae, having four toes on each foot and selenodont teeth, the remains of which are found in Middle Tertiary rocks in the western United States; (also) an animal of this genus. Later chiefly in Oreodon beds: strata containing fossils of these animals", Mid 19th cent.; earliest use found in Proceedings of the Academy of Natural Sciences of Philadelphia. From scientific Latin Oreodon from Hellenistic Greek ὀρεο- + ancient Greek -όδον.[Oreodon etymology, Oreodon origin, 英语词源]