plural noun Pel·y·co·sau·ria

Definition of Pelycosauria

  1. :  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

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Origin and Etymology of pelycosauria

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

Seen and Heard

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a rounded knoll or a ridge of ice

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