[ joo-ras-ik ]
/ dʒʊˈræs ɪk /


noting or pertaining to a period of the Mesozoic Epoch, occurring from 190 to 140 million years ago and characterized by an abundance of dinosaurs and the advent of birds and mammals.


the Jurassic Period or System.

Origin of Jurassic

1825–35; Jur(a) + -assic, suffix extracted from Triassic; compare French jurassique


post-Ju·ras·sic, adjective
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Examples from the Web for jurassic

British Dictionary definitions for jurassic

/ (dʒʊˈræsɪk) /


of, denoting, or formed in the second period of the Mesozoic era, between the Triassic and Cretaceous periods, lasting for 55 million years during which dinosaurs and ammonites flourished


the Jurassic the Jurassic period or rock system

Word Origin for Jurassic

C19: from French jurassique, after the Jura (Mountains)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Science definitions for jurassic

[ ju-răsĭk ]

The second and middle period of the Mesozoic Era, from about 208 to 144 million years ago. During this time the supercontinent Pangaea continued to split up and numerous shallow seas inundated the new continents. Dinosaurs were the dominant form of terrestrial animal life, and the earliest birds appeared. Marine life was dominated by ammonites and belemnites, and sponges, corals, bryozoa, and gastropods all flourished. Gymnosperms and cycads were the dominant land plants. See Chart at geologic time.
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