Definition of pelycosaur
: any of an order (Pelycosauria) of primitive chiefly Permian quadruped synapsid reptiles often having extreme development of the dorsal vertebral processes
Origin of pelycosaur
ultimately from Greek pelyc-, pelyx bowl + sauros lizard
First Known Use: 1904
Learn More about pelycosaur
Britannica.com: Encyclopedia article about "pelycosaur"
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