plesiosaurus

noun

ple·​si·​o·​sau·​rus

ˌplēsēəˈsȯrəs

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

Word History

Etymology

New Latin, from plesi- + -saurus

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