plural noun The·rap·si·da \-sədə\

Definition of Therapsida

  1. :  an order of synapsid reptiles that flourished during the Permian and Triassic periods with the last forms becoming extinct during the Cretaceous Reptiles of the order Therapsida are considered ancestors of the mammals.

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Origin and Etymology of therapsida

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

Seen and Heard

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feeling or affected by lethargy

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