Triassic Definition

Triassic
adj

1. Belonging, relating or referring to the earliest period of the Mesozoic era when the first dinosaurs, large sea reptiles and small mammals appeared and conifers became widespread, forming luxuriant forests.
2. The name for the series of rock strata that lies beneath the Jurassic and above the Permian.

noun

1. This period or rock system.

Etymology: 19c: from Latin trias triad, so called because the period is divisible into three distinct sections.