Therapsida

plural noun

The·​rap·​si·​da

-sədə

: an order of synapsid reptiles that flourished during the Permian and Triassic periods with the last forms becoming extinct during the Cretaceous

Note: Reptiles of the order Therapsida are considered ancestors of the mammals.

Word History

Etymology

New Latin, from Greek theraps attendant + New Latin -ida

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