plesiosaur

== English == === Etymology === Backformation of translingual Plesiosaurus, named by William Conybeare and Henry De la Beche in 1824 because plesiosaurs were more like a normal reptile than Ichthyosaurus, which had been found in the same rock strata a few years earlier. Surface derivation, plesio- +‎ -saur. === Pronunciation === IPA(key): /ˈpliːsiəsɔːɹ/ === Noun === plesiosaur (plural plesiosaurs) Any of the order †Plesiosauria of extinct marine reptiles, from the Jurassic and Cretaceous periods. [from c. 1840] ==== Translations ====