Jurassic

a.

1.

(Geol.) Of the age of the middle Mesozoic, about 190 to 140 million years ago, including, as divided in England and Europe, the Lias, Oölite, and Wealden; - named from certain rocks of the Jura mountains. It was noted for the predominance of dinosaurs on land, and the development of the first birds and mammals.

Noun

1.

Jurassic - from 190 million to 135 million years ago; dinosaurs; conifers Synonyms: Jurassic period

Age of Reptiles, geological period, Jurassic period, Mesozoic, Mesozoic era, period