1. Of or relating to or denoting the first period of the Mesozoic era
   "The Triassic period saw the emergence of the first dinosaurs"

1. The earliest period of the Mesozoic era, from about 252 to 201 million years ago; characterized by the emergence of dinosaurs, marine reptiles and significant volcanic activity
   - Triassic period

Type of: geological period, period

Part of: Age of Reptiles, Mesozoic, Mesozoic era

Encyclopedia: Triassic