cotylosaur

noun

co·​ty·​lo·​saur ˈkä-tə-lō-ˌsȯr 

-lə-ˌsȯr,

kə-ˈti-lə-

: 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

Word History

Etymology

ultimately from Greek kotylē + sauros lizard

First Known Use

1895, in the meaning defined above