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Jurassic

American  
[joo-ras-ik] / dʒʊˈræs ɪk /

adjective

  1. 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.

noun

  1. the Jurassic Period or System.

Jurassic British  
/ dʒʊˈræsɪk /

adjective

  1. 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

"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

noun

  1. the Jurassic period or rock system

"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
Jurassic Scientific  
/ j-răs′ĭk /

  1. 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.

  2. See Chart at geologic time

Other Word Forms

  • post-Jurassic adjective

Etymology

Origin of Jurassic

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The valley spreads out in front of you in what has to be one of England’s finest views, all the way to the golden cliffs of the Jurassic Coast.

From The Wall Street Journal • Apr. 11, 2026

Current evidence now suggests that octopuses appeared much later, during the Jurassic period.

From Science Daily • Apr. 7, 2026

The show saw Wicked and Jurassic Park star Goldblum talking about his new album, Night Blooms, the latest offering from his band, The Mildred Snitzer Orchestra.

From BBC • Mar. 14, 2026

"That's your Jurassic Park moment... one to remember for a lifetime."

From Barron's • Feb. 27, 2026

It was like being inside that movie Jurassic Park.

From "Mr. Lemoncello's Library Olympics" by Chris Grabenstein

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.