ple·​si·​o·​saur | \ ˈplē-sē-ə-ˌsȯr How to pronounce plesiosaur (audio) , -zē- \

Definition of plesiosaur

: any of an order or suborder (Plesiosauria) of large carnivorous marine reptiles of the Mesozoic with dorsoventrally flattened bodies and limbs modified into flippers

Examples of plesiosaur in a Sentence

Recent Examples on the Web That book also claims that Noah likely took small, or baby, dinosaurs onto his ark and that the Loch Ness Monster likely was real, perhaps a plesiosaur — a marine reptile that scientists say became extinct at the same time as dinosaurs. Chris Hays,, 9 Aug. 2021 Her discoveries in Jurassic paleontology, including several ichthyosaur specimens and the first plesiosaur, would have staggering implications at a time when Christians commonly believed the earth was about 6,000 years old. Josephine Livingstone, The New Republic, 27 Jan. 2021 Neither did the squidlike ammonites that curled like rams’ horns, or marine reptiles including the plesiosaurs (Loch Ness conspiracies notwithstanding). Quanta Magazine, 25 Mar. 2020 This includes Ichthyosaurs, plesiosaurs, and even the Megalodon – the largest shark known to man. Matthew Cox,, 13 Mar. 2020 While other marine reptiles such as porpoise-like ichthyosaurs and long-necked plesiosaurs had the evolutionary flexibility to expand into deeper ocean environments, hyper-specialized thalattosaurs like Gunakadeit may have struggled to follow suit. Katherine J. Wu, Smithsonian Magazine, 5 Mar. 2020 Elasmosaurs make up a family of the plesiosaurs, which represent some of the largest sea creatures of the Cretaceous. National Geographic, 7 June 2019 The legend of the Loch Ness monster has commonly been attributed to a plesiosaur that somehow managed to survive the mass extinction event that killed off the dinosaurs. Fox News, 6 Sep. 2019 Some believe Nessie is a long-necked plesiosaur-like an elasmosaur - that somehow survived when all the other dinosaurs were wiped out. Fox News, 11 June 2019

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

1839, in the meaning defined above

History and Etymology for plesiosaur

ultimately from Greek plēsios close (akin to Greek pelas near) + sauros lizard

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The first known use of plesiosaur was in 1839

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Cite this Entry

“Plesiosaur.” Dictionary, Merriam-Webster, Accessed 20 Oct. 2021.

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