Definitions

1. noun

A member of the subphylum Chordata, especially one of the vertebrate animals that lived during the Mesozoic Era, such as dinosaurs, pterosaurs, and early mammals.

“The museum had an impressive collection of Mesozoan fossils on display.”

2. adjective

Relating to or characteristic of the Mesozoic Era.

“The Mesozoan landscape featured vast deserts and towering volcanoes.”