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.

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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

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noun

1. the Jurassic period or rock system

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

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Other Word Forms

• post-Jurassic
  adjective

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Etymology

Origin of Jurassic

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

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Example Sentences

See Examples For:

Jurassic

"The new species Megacauda sungei is the largest of the mammaliaforms from the Jurassic," says Thomas Martin.

From Science Daily ● Oct. 13, 2026

Other Jurassic docodont fossils show that members of this group were already adapting to very different environments.

From Science Daily ● Oct. 13, 2026

If you’re looking for action and adventure, Sam calls The End of Oak Street a “nasty little throwback to Jurassic Park.”

From Slate ● Sep. 4, 2026

On a summer morning before the heat set in, he pointed out the spot where his flock of over a dozen birds once roamed, strutting across the sand like remnants of the Jurassic era.

From Los Angeles Times ● Sep. 3, 2026

Jurassic refers to the Jura Mountains on the border of France and Switzerland.

From "A Short History of Nearly Everything" by Bill Bryson

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