Definition of Permo–Triassic in English:

Permo–Triassic

adjective

Geology
  • 1Relating to or denoting the boundary of the Permian and Triassic periods, about 245 million years ago. Mass extinctions occurred at this time, marking the end of the Palaeozoic era.

    1. 1.1as noun the Permo–Triassic" or "Permo–Trias The Permian and Triassic periods together or the system of rocks deposited during them.