plural noun

: an order of primitive Permian reptiles (subclass Synapsida) that resemble mammals and often have extreme development of the dorsal vertebral processes compare dimetrodon, edaphosaurus
adjective or noun

Word History


New Latin, from pelyco- (from Greek pelyk-, pelyx wooden bowl) + -sauria

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Dictionary Entries Near Pelycosauria

Cite this Entry

“Pelycosauria.” Dictionary, Merriam-Webster, Accessed 16 Jun. 2024.

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