Triassic
Syllabification: (Tri·as·sic)
Pronunciation: /trīˈasik/
Definition of Triassic
adjective
Geology- of, relating to, or denoting the earliest period of the Mesozoic era, between the Permian and Jurassic periods. See also Permo–Triassic.
The Triassic lasted from about 245 million to 208 million years ago. Many new organisms appeared following the mass extinctions of the end of the Paleozoic era, including the earliest dinosaurs and ammonites and the first primitive mammals