Meaning of ARCHOSAUR in English

Any of the various advanced pterosaurs , dinosaurs , birds, and crocodilians.

The first known archosaurs appeared 242–227 million years ago during the {{link=Triassic Period">Triassic Period . All early archosaurs possessed an ankle specialization that aided in upright posture, and most had long hindlegs and short forelimbs. Unlike the teeth of earlier reptiles, which were set in a shallow groove, the teeth of archosaurs were (and are) set in sockets.

Britannica English dictionary.      Английский словарь Британика.