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

The newly studied fossil was uncovered during excavations led by Fundación Dinópolis at the "Están de Colón" site within the Villar del Arzobispo Formation, which dates back to the Late Jurassic period.

From Science Daily • May 17, 2026

The discovery could help scientists better understand how giant sauropods evolved across the Southern Hemisphere during the Late Jurassic period.

From Science Daily • May 12, 2026

From teaching children in Hampshire about insects to searching for fossils on Dorset's Jurassic Coast, Sir David's trips to the south reflect his enduring desire to share knowledge.

From BBC • May 8, 2026

The New Zealander, who starred as Dr Alan Grant in the 1993 blockbuster "Jurassic Park", revealed in a 2023 memoir he was "possibly dying" with stage-three non-Hodgkin lymphoma.

From Barron's • Apr. 29, 2026

Most of these are also reasonably well known: Cretaceous, Jurassic, Triassic, Silurian, and so on.*

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