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

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In the latter, the absurdly gigantic mosasaur (which technically wasn’t even a dinosaur) snacking on great white sharks didn’t grow longer than about 50 feet from head to tail. Katherine J. Wu, Smithsonian, "Five Ways Real Science Would Make the New Jurassic World So Much Better," 12 June 2018 Existing in a warm, shallow seaway between today’s Rocky and Appalachian mountains, plesiosaurs lived alongside mosasaurs, the apex predator of their day, resembling a type of watery Komodo dragon. Jack Dura, The Seattle Times, "80 million-year-old remains prepped for North Dakota display," 15 Jan. 2018 The plesiosaur to be displayed will be positioned by a mosasaur specimen. Jack Dura, The Seattle Times, "80 million-year-old remains prepped for North Dakota display," 15 Jan. 2018 But big things in the ocean, like mosasaurs, which weren’t actually dinosaurs, all go extinct. Mike Hettwer, National Geographic, "Why T. Rex's Puny Arms Are a Sign of Strength," 30 Sep. 2017 At Pembina Gorge (Aug. 8 to 12), volunteers can dig up sea life from 80 million years ago, like giant squid and mosasaurs (marine reptiles). Hillary Richard, New York Times, "When Dinosaurs Roamed North Dakota," 11 July 2017 The mosasaur’s skull sat in the prep lab of the New Jersey State Museum. Brian Switek, WIRED, "Mosasaur Bites and Limpet Scrapes," 11 Apr. 2012

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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The first known use of mosasaur was in 1841

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to affect and impair by alcohol or a drug

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