: any of a subclass (Archosauria) of reptiles comprising the dinosaurs, pterosaurs, and crocodilians

Examples of archosaur in a Sentence

Recent Examples on the Web
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During the Triassic, a broad group known as the archosaurs evolved and eventually split into two major lineages. Sean Mowbray, Discover Magazine, 1 Aug. 2024 Nesbitt says that these small differences are what paleontologists expected to find, especially as researchers find fossils that sit closer to the common ancestor of all archosaurs. Joshua Rapp Learn, Discover Magazine, 15 Aug. 2023

Word History

Etymology

New Latin Archosauria, from Greek archōn + sauros lizard

First Known Use

1933, in the meaning defined above

Time Traveler
The first known use of archosaur was in 1933

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Cite this Entry

“Archosaur.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/archosaur. Accessed 24 Mar. 2025.

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