noun ple·si·o·sau·rus

Definition of plesiosaurus

  1. 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. 2 plural plesiosauri \-ȯˌrī\ :  any reptile of the genus Plesiosaurus

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Origin and Etymology of plesiosaurus

New Latin, from plesi- + -saurus

Seen and Heard

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a brief usually trivial fact

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