The Era of the Dinosaurs is a period in Earth's history that lasted from about 252 million to 66 million years ago. This era is also known as the Mesozoic, which is an 8-letter word that can be found in crosswords. During this time, dinosaurs were the dominant species on the planet and many other species evolved and went extinct. The Mesozoic Era is divided into three periods: Triassic, Jurassic, and Cretaceous. Each period had its own unique characteristics and saw the evolution of different species.