D defs.my
Entry 1 sense Webster, 1913

Plesiosaurus

· Ple·si·o·sau·rus · IPA
01 n. A genus of large extinct marine reptiles, having a very long neck, a small head, and paddles for swimming. It lived in the Mesozoic age.
pl. Plesiosauri ((#))
  1. 1.
    A genus of large extinct marine reptiles, having a very long neck, a small head, and paddles for swimming. It lived in the Mesozoic age.(Paleon.)