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Definition of plesiosaur

plesiosaur

/ˈpliː.si.əˌsɔːr/
ple · si · o · saur
Plural:plesiosaurs
•
Adjective:plesiosaurian
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plesiosaur Lexical Profile

plesiosaur Game Scores & Validity

• noun

1

A large, extinct marine reptile of the Mesozoic era, typically characterized by a broad flat body, large paddle-like flippers, and a long neck with a relatively small head.

Example

"The paleontology museum unveiled a beautifully preserved fossil of a plesiosaur, showcasing its distinctively long neck and powerful flippers."

Synonyms
View all synonyms for plesiosaur

Word Nuance & Usage

Although frequently grouped with them in popular culture, the plesiosaur is not a true dinosaur, but rather a distinct type of marine reptile that lived alongside them.

• Nearby Words

plecostomus
plectranthus
pleione
plesiosaur
pliers
pliosaur
plitvice

Word Origin & Etymology

Coined in the early 19th century from the Greek 'plēsios' (near) and 'sauros' (lizard), named to imply it was closer in form to modern reptiles than the previously discovered ichthyosaur.

Usage Trend

Historical frequency of usage in published text.

180019102020
Data source: Google Books Ngram Viewer

Cite this Entry

Wordmom. (2026). Definition of Plesiosaur. In Wordmom Dictionary. Retrieved Oct 18, 2026, from https://wordmom.com/dictionary/plesiosaur
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