pel·y·co·saur | \ ˈpe-li-kə-ˌsȯr 
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\Definition of pelycosaur
: any of an order (Pelycosauria) of extinct, primitive, synapsid vertebrates (such as dimetrodon) chiefly of the Permian period often having extreme development of the dorsal vertebral processes and giving rise to the therapsids
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Time Traveler for pelycosaur
The first known use of pelycosaur was in 1884
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