ple·si·o·saur (plēsē-ə-sôr, plēzē-)
n. pl. ple·si·o·saurs
Any of various extinct marine reptiles of the group Plesiosauria of the Mesozoic Era, having paddlelike limbs, a short tail, and sometimes a very long neck.
[New Latin Plēsiosaurus, type genus : Greek plēsios, near to; see pel-5 in the Appendix of Indo-European roots + Greek sauros, lizard.]
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