mo·​sa·​saur | \ ˈmō-zə-ˌsȯr How to pronounce mosasaur (audio) \

Definition of mosasaur

: any of a family (Mosasauridae) of very large extinct marine fish-eating lizards of the Upper Cretaceous with limbs modified into paddles that are related to the recent monitor lizards

Examples of mosasaur in a Sentence

Recent Examples on the Web Paleontologists don’t know for sure the egg came from a mosasaur. Alex Fox, Smithsonian Magazine, "First Soft-Shelled Dinosaur Egg Fossils Found," 22 June 2020 The second discovery is another soft-shelled egg that researchers have attributed to a kind of giant marine reptile called a mosasaur. Alex Fox, Smithsonian Magazine, "First Soft-Shelled Dinosaur Egg Fossils Found," 22 June 2020 The bones of a mosasaur were found less than 700 feet from the site, suggesting the egg may have belonged to these 20-foot-long swimming reptiles. Michael Greshko, National Geographic, "First soft-shelled dinosaur eggs shed light on prehistoric parenting," 17 June 2020 Turns out, the fossil was a soft-shell egg — the largest-ever discovered — possibly laid by a massive marine reptile known as the mosasaur. Joshua Bote, USA TODAY, "'The Thing': Scientists reveal world's biggest soft-shelled egg belongs to extinct sea lizard," 19 June 2020 Based on an analysis of 259 modern reptiles and their eggs, an ancient beast known as a mosasaur would seem to match description, according to SWNS. Fox News, "World’s largest reptile egg discovered on Antarctica," 18 June 2020 The oceans were still dominated by other marine animals like sharks, rays, and aquatic reptiles like mosasaurs. Sara Kiley Watson, Popular Science, "Most dinosaurs didn’t swim—but this ‘dino equivalent of Jaws’ sure did," 14 May 2020 Despite the fact that mosasaurs and plesiosaurs terrorized the ancient oceans of the planet, they are not considered dinosaurs. Fox News, "Terrifying Spinosaurus had powerful tail, becoming first known dinosaur to live underwater," 30 Apr. 2020 Most Mesozoic-Era ocean-dwelling creatures were actually marine reptiles called plesiosaurs, ichthyosaurs, or mosasaurs, which, despite their appearance, are not considered dinosaurs. Katherine J. Wu, Smithsonian Magazine, "Groundbreaking Fossil Suggests Spinosaurus Is First Known Swimming Dinosaur," 30 Apr. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mosasaur.' 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 mosasaur

1841, in the meaning defined above

History and Etymology for mosasaur

New Latin Mosasaurus, from Latin Mosa the river Meuse + Greek sauros lizard

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Time Traveler for mosasaur

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The first known use of mosasaur was in 1841

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Last Updated

4 Sep 2020

Cite this Entry

“Mosasaur.” Dictionary, Merriam-Webster, Accessed 21 Oct. 2020.

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