cotylosaurian
/kəˌtʌɪləˈsɔːrɪən/Palaeontology
adjective
Belonging to, characteristic of, or designating the order Cotylosauria of extinct reptiles.
noun
A reptile of the order Cotylosauria; a cotylosaur. Now rare.
Origin
Late 19th century; earliest use found in Transactions of the American Philosophical Society. From scientific Latin Cotylosauria, order name + -an. With use as noun compare slightly earlier cotylosaur.