Home › Words › I › ichthyosaurichthyosaur/ˈɪkθiəsɔːɹ/ichthyosaur means any fishlike marine reptiles of the extinct order †Ichthyosauria of the early Triassic to the late Cretaceous period, that had a body somewhat like a porpoise.ichthyosaur is pronounced /ˈɪkθiəsɔːɹ/.EtymologyBorrowed from translingual Ichthyosaurus, equivalent to Ancient Greek ἰχθύς (ikhthús, “fish”) + Ancient Greek σαῦρος (saûros, “lizard”).nounAny fishlike marine reptiles of the extinct order †Ichthyosauria of the early Triassic to the late Cretaceous period, that had a body somewhat like a porpoise.e.g.“The most striking marine reptiles are the fishlike or porpoiselike ichthyosaurs.” — 2013, F. Crescitelli, The Visual System in Vertebrates, page 27:Definitions & examples from Wiktionary (CC BY-SA 3.0).Words closest in meaningBy meaning, not spelling — each word's AI semantic fingerprint, nearest first.ichthyopterygian 81% match — Any of the superorder †Ichthyopterygia of extinct marine reptiles, superficially resembling dolphins. vs ichthyosaur →ichthyosauromorph 78% match — Any extinct marine reptile of the clade †Ichthyosauromorpha vs ichthyosaur →ichthyosaurus 76% match — Any members of the genus Ichthyosaurus. vs ichthyosaur →ichthyosaurian 73% match — Of or relating to the Ichthyosauria. vs ichthyosaur →plesiosaur 71% match — Any of the order †Plesiosauria of extinct marine reptiles, from the Jurassic and Cretaceous periods. vs ichthyosaur →ichthyodectid 68% match — Any member of the family †Ichthyodectidae of extinct predatory fish principally of the Cretaceous. vs ichthyosaur →neoichthyosaur 66% match — Any ichthyosaur of the former clade Neoichthyosauria vs ichthyosaur →phytosaurian 65% match — Any of the order †Phytosauria of extinct crocodilian-like archosauriforms or basal archosaurians from the Late Triassic. vs ichthyosaur →