Jurassic a. : Of the age of the middle Mesozoic, including, as divided in England and Europe, the Lias, Oolite, and Wealden; -- named from certain rocks of the Jura mountains.

Jurassic n. : The Jurassic period or formation; -- called also the Jura.

Example:
How do you change the maximum amount of fences in Jurassic Park Operation Genesis for the PC?

Taxonomy
Jurassic, Jurassic period, Late Jurassic, marine, Geology, duration, dinosaurs, Jurassic strata, free encyclopedia, Africa, Early Jurassic, Jura, calcitic, Hardie, London, conifer, Swiss Jura, Fauna.

Defination from the web:
Jurassic Period, a major unit of the geologic timescale that extends from about 200 million years ago, at the end of the Triassic to 146 million years ago, at the beginning of the Cretaceous.