Definition of Archosauria
: 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\ play adjective or noun
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Origin and Etymology of archosauria
New Latin, from archo- (from Greek archōn) + -sauria
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