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Any of various vertebrates of the group Archosauria, having a single opening in each side of the skull in front of the eye socket, and including the dinosaurs, birds, pterosaurs, and modern crocodilians.

[New Latin Archosauria, subclass name : Greek arkhos, ruler + Greek sauros, lizard.]

ar′cho·saur′i·an n. & adj.


belonging to or characteristic of the archosaurs
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.archosaurian - extinct reptiles including: dinosaursarchosaurian - extinct reptiles including: dinosaurs; plesiosaurs; pterosaurs; ichthyosaurs; thecodonts
diapsid, diapsid reptile - reptile having a pair of openings in the skull behind each eye
Archosauria, subclass Archosauria - a large subclass of diapsid reptiles including: crocodiles; alligators; dinosaurs; pterosaurs; plesiosaurs; ichthyosaurs; thecodonts
dinosaur - any of numerous extinct terrestrial reptiles of the Mesozoic era
flying reptile, pterosaur - an extinct reptile of the Jurassic and Cretaceous having a bird-like beak and membranous wings supported by the very long fourth digit of each forelimb
thecodont, thecodont reptile - presumably in the common ancestral line to dinosaurs and crocodiles and birds
ichthyosaur - any of several marine reptiles of the Mesozoic having a body like a porpoise with dorsal and tail fins and paddle-shaped limbs
plesiosaur, plesiosaurus - extinct marine reptile with a small head on a long neck a short tail and four paddle-shaped limbs; of the Jurassic and Cretaceous
nothosaur - extinct marine reptile with longer more slender limbs than plesiosaurs and less completely modified for swimming
Adj.1.archosaurian - of or relating to reptiles of the subclass Archosauriaarchosaurian - of or relating to reptiles of the subclass Archosauria
References in periodicals archive ?
In addition, the possibility of a dual origin of avian flapping flight may underlie the thinking of Evgeny Kurochkin when he proposed independent origins of Archaeopteryx and the enaniornithines versus the ornithurines from different groups of archosaurian reptiles (footnote 111, p.
Archosaurian reptiles from the Evangeline Member comprise various taxa of crocodile-line archosaurs (Pseudosuchia) (Figs.