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

Etymology

Origin of Jurassic

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

Example Sentences

Tracks from the Triassic and Jurassic periods are common in Lesotho and nearby regions of South Africa, including the Free State and Eastern Cape.

From Science Daily • Apr. 24, 2026

That group has an evolutionary history stretching back around 230 million years to the early Jurassic.

From BBC • Apr. 22, 2026

In this case, the textures appeared to preserve a dense layer of microbial life that existed more than 180 million years ago during the Early Jurassic.

From Science Daily • Apr. 3, 2026

Now we’re on Vegas World; now we’re on Jurassic Planet; now we’re on a planet ruled by a gigantic queen bee.

From The Wall Street Journal • Mar. 31, 2026

A phrase he’d learned from movies—well, a movie, Jurassic Park.

From "Millionaires for the Month" by Stacey McAnulty