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 (plē′sē-ə-sôr′, plē′zē-)
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- in Indo-European roots + Greek sauros, lizard.]


(Palaeontology) any of various extinct marine reptiles of the order Sauropterygia, esp any of the suborder Plesiosauria, of Jurassic and Cretaceous times, having a long neck, short tail, and paddle-like limbs. See also ichthyosaur Compare dinosaur, pterosaur
[C19: from New Latin plēsiosaurus, from Greek plēsios near + sauros a lizard]


(ˈpli si əˌsɔr)

any extinct marine reptile of the Jurassic and Cretaceous suborder Plesiosauroidea, having a thick body and paddlelike limbs.
[< New Latin Plesiosaurus (1821) genus name < Greek plēsí(os) near, close to + -o- -o- + saûros -saur]
ple`si•o•sau′roid, adj.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.plesiosaur - extinct marine reptile with a small head on a long neck a short tail and four paddle-shaped limbsplesiosaur - extinct marine reptile with a small head on a long neck a short tail and four paddle-shaped limbs; of the Jurassic and Cretaceous
archosaur, archosaurian, archosaurian reptile - extinct reptiles including: dinosaurs; plesiosaurs; pterosaurs; ichthyosaurs; thecodonts
genus Plesiosaurus - a reptile genus of suborder Plesiosauria
References in classic literature ?
There were huge tortoises too, paddling about among these other reptiles, which Perry said were Plesiosaurs of the Lias.
The thing must have been sixteen or eighteen feet in length and closely resembled pictures I had seen of restored plesiosaurs of the lower Jurassic.
It was obvious the fossil was fingers or toes, because there were three in a row, but the first thing that came to mind was that it was some sort of plesiosaur.
The elusive Nessie is commonly portrayed as looking like a plesiosaur.
A Plesiosaur Broke My Bathtub follows the adventures of Thomas and Molly who find themselves face to face with a life-size, real-life plesiosaur in the town's local lake.
Famed fossil hunter Mary Anning discovered the world's first complete plesiosaur along this coast in 1823, a dozen years after her family uncovered the first ichthyosaur.
It belonged to a plesiosaur, a huge marine reptile that lived in the southern ocean when the planet was much warmer than it is today, reported New Tang Dynasty Television.
95); Random House Saurus Street 5 & 6 A Plesiosaur Broke My Bathtub & A Diplodocus Trampled My Tepee Nick Falk/Tony Flowers ($12.
In 2003, a fossilised vertebra of a plesiosaur was found on the shore of Loch Ness.