[mez-uh-zoh-ik, mes-, mee-zuh-, -suh-] 
Geology| 1. | noting or pertaining to an era occurring between 230 and 65 million years ago, characterized by the appearance of flowering plants and by the appearance and extinction of dinosaurs. |
| 2. | the Mesozoic Era or group of systems. |
| Mes·o·zo·ic (měz'ə-zō'ĭk, měs'-) adj. Of, belonging to, or designating the era of geologic time that includes the Triassic, Jurassic, and Cretaceous periods and is characterized by the development of flying reptiles, birds, and flowering plants and by the appearance and extinction of dinosaurs. See Table at geologic time. n. The Mesozoic Era. |
| Mesozoic (měz'ə-zō'ĭk) Pronunciation Key
The era of geologic time from about 245 to 65 million years ago. The Mesozoic Era was characterized by a drastic change in plants and animals. In the early part of the Mesozoic, ferns, cycads, and ginkgos were dominant; later, gymnosperms and angiosperms developed. Dinosaurs also first appeared in the Mesozoic and, with the exception of birds, became extinct at the end of the era. See Chart at geologic time. |
əˈzoʊ