noun aeto·saur \ā-ˈe-tə-ˌsȯr\

Definition of aetosaur



  1. :  any of an order or suborder (Aetosauria) of extinct, chiefly herbivorous, armored reptiles that lived during the late Triassic period and had a long, narrow body, a small head, and a flat, piglike snout … footprints (actually scrape marks) can also be identified as coming from two other large vertebrates: phytosaurs and aetosaurs, crocodile-like reptiles who lived around the shallow lake. — Jeanne Nicholson Siler, Washington Post, 2 Nov. 1990 Aetosaurs were low-slung animals 1 to 5 metres long with small heads and armoured bodies, built like the ankylosaurs of the dinosaur age or the extinct, car-sized armadillos that died out around 10,000 years ago. — Jeff Hecht, New Scientist, 25 Feb. 2006 Aetosaurs are archosaurs that are closely related to the crocodilians.

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Origin and Etymology of aetosaur

borrowed from New Latin Aëtosauria, from Aëtosaurus aetosaurus + -ia 2-ia

First Known Use: 1893

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capable of being understood in two ways

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