Pronunciation: (trī-as'ik), [key] Geol.
noting or pertaining to a period of the Mesozoic Era, occurring from 230 to 190 million years ago and characterized by the advent of dinosaurs and coniferous forests. See table under geologic time.
Also,Tri•asPronunciation: (trī'us) [key]the Triassic Period or System.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.