plural noun

Definition of Plesiosauria

1 : a suborder of Sauropterygia comprising Mesozoic marine reptiles with dorsoventrally flattened bodies and limbs modified into paddles — compare plesiosaurus
2 in some classifications : an order of Reptilia nearly coextensive with Sauropterygia

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Other Words from Plesiosauria

plesiosaurian \ ¦⸗⸗⸗¦sȯrēən \ adjective or noun
plesiosauroid \ -​ȯˌrȯid \ adjective

History and Etymology for Plesiosauria

New Latin, from plesi- + -sauria

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Cite this Entry

“Plesiosauria.” The Dictionary, Merriam-Webster Inc., Accessed 21 January 2020.

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