/joo ras"ik/ , Geol.
adj.
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. See table under geologic time .
n.
2. the Jurassic Period or System.
[ 1825-35; JUR(A) + -assic, suffix extracted from TRIASSIC; cf. F jurassique ]