ar·​cho·​saur | \ ˈär-kə-ˌsȯr How to pronounce archosaur (audio) \

Definition of archosaur

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

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Other Words from archosaur

archosaurian \ ˌär-​kə-​ˈsȯr-​ē-​ən How to pronounce archosaur (audio) \ adjective or noun

Examples of archosaur in a Sentence

Recent Examples on the Web But this itty-bitty reptile from Madagascar is related to some of the largest animals that ever walked the planet, belonging to the archosaur subgroup that led to dinosaurs and their flying relatives, the pterosaurs. Riley Black, National Geographic, "How the world's deadliest mass extinction actually helped the rise of dinosaurs," 11 Sep. 2020 The earliest dinosaurs were not ravenous creatures that directly outcompeted their archosaur relatives, as experts used to think. Riley Black, National Geographic, "How the world's deadliest mass extinction actually helped the rise of dinosaurs," 11 Sep. 2020 Different reef-building creatures began to take hold, and lush vegetation covered the land, setting the stage for a group of reptiles called the archosaurs: the forerunners of birds, crocodilians, pterosaurs, and the nonavian dinosaurs. Michael Greshko, National Geographic, "What are mass extinctions, and what causes them?," 30 Sep. 2019 This came as a surprise, Stocker says, and indicates that the more complex, crocodile-type ankle shape was ancestral for archosaurs. Brian Switek, Smithsonian, "Before There Were Dinosaurs, There Was This Weird Crocodile-Looking Thing," 12 Apr. 2017 Looking at the diversity of living and extinct archosaurs Brian Switek, WIRED, "When Pseudo-Crocs Walked Tall," 8 Oct. 2010 Snakes and scaly lizards split from the archosaur before turtles and lack the red oil on their retinas. Joanna Klein, New York Times, "Some Turtles See Red Better Than You Do," 19 Aug. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'archosaur.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of archosaur

1933, in the meaning defined above

History and Etymology for archosaur

New Latin Archosauria, from Greek archōn + sauros lizard

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Time Traveler for archosaur

Time Traveler

The first known use of archosaur was in 1933

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Cite this Entry

“Archosaur.” Dictionary, Merriam-Webster, Accessed 27 Feb. 2021.

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