'Jurassic' definitions:
Definition of 'Jurassic'
From: WordNet
adjective
Of or relating to or denoting the second period of the Mesozoic era
noun
From 190 million to 135 million years ago; dinosaurs; conifers [syn: Jurassic, Jurassic period]
Definition of 'Jurassic'
From: GCIDE
- Jurassic \Ju*ras"sic\, a. (Geol.) Of the age of the middle Mesozoic, about 190 to 140 million years ago, including, as divided in England and Europe, the Lias, O["o]lite, 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. -- n. The Jurassic period or formation; -- called also the Jura. [1913 Webster +PJC]