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co·ty·lo·saur | \ ˈkä-tə-lō-ˌsȯr 
, -lə-ˌsȯr, kə-ˈti-lə-\
, -lə-ˌsȯr, kə-ˈti-lə-\Definition of cotylosaur
: any of an order (Cotylosauria) of extinct primitive reptiles of the Carboniferous to Triassic with short legs and massive bodies that were probably the earliest truly terrestrial vertebrate animals
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The first known use of cotylosaur was in 1895
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