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therapsid

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noun the·rap·sid \thə-ˈrap-səd\

Definition of therapsid

  1. :  any of an order (Therapsida) of synapsid reptiles that flourished during the Permian and Triassic periods with the last forms becoming extinct during the Cretaceous period and that are cconsidered ancestors of the mammals

therapsid

adjective

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Origin and Etymology of therapsid

New Latin Therapsida, from ther- mammal (from Greek thēr wild animal) + apsid-, apsis arch, vault — more at fierce, apsis

Learn More about therapsid

  1. Britannica.com: Encyclopedia article about therapsid

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