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
plural plesiosauri
: any reptile of the genus Plesiosaurus

Word History


New Latin, from plesi- + -saurus

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Dictionary Entries Near plesiosaurus

Cite this Entry

“Plesiosaurus.” Dictionary, Merriam-Webster, Accessed 24 Jun. 2024.

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