Merycoidodontidae

plural noun

Mer·​yc·​oi·​do·​don·​ti·​dae ˌmer-ē-ˌkȯi-də-ˈdän-tə-ˌdē 

: a family of extinct artiodactyl mammals comprising the oreodonts of North America

Word History

First Known Use

1908, in the meaning defined above

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