Archosauria

plural noun

Ar·​cho·​sau·​ria

ˌär-kə-ˈsȯr-ē-ə

: a large subclass of Reptilia comprising the dinosaurs, pterosaurs, and crocodilians all distinguished by possessing temporal openings separated from each other by a postorbitosquamosal arch

archosaurian

¦ar-kə-¦sȯr-ē-ən 

adjective or noun

Word History

Etymology

New Latin, from archo- (from Greek archōn) + -sauria

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