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noun pel·y·co·saur \ˈpe-li-kə-ˌsȯr\

Definition of pelycosaur

  1. :  any of an order (Pelycosauria) of primitive chiefly Permian quadruped synapsid reptiles often having extreme development of the dorsal vertebral processes

Origin and Etymology of pelycosaur

ultimately from Greek pelyc-, pelyx bowl + sauros lizard

First Known Use: 1904

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