plesiosaurus

noun
ple·​si·​o·​sau·​rus

Definition of plesiosaurus

1 capitalized : a genus of marine reptiles (suborder Plesiosauria) of the Mesozoic of Europe and North America having a very long neck, a small head, and all four limbs developed as paddles for swimming
2 plural plesiosauri\ -​ȯˌrī \ : any reptile of the genus Plesiosaurus

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History and Etymology for plesiosaurus

New Latin, from plesi- + -saurus

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Cite this Entry

“Plesiosaurus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/plesiosaurus. Accessed 20 Sep. 2020.

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