n. Any of various extinct aquatic reptiles of the group Sauropterygia that flourished during the Mesozoic Era and included the plesiosaurs. [From New Latin Sauropterygia, superorder name : Greek sauros, lizard + Greek pterux, pterug-, wing, flipper; see pet- in the Appendix of Indo-European roots.] saur·op′ter·ygi·an adj. |
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