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Plesiosauria

plural noun Ple·si·o·sau·ria

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
—

plesiosaurian

adjective or noun
—

plesiosauroid

\-ȯˌrȯid\ adjective

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Origin and Etymology of plesiosauria

New Latin, from plesi- + -sauria

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