cenozoic — of, denoting, or relating to the most recent geological era, which began 65 000 000 years ago: characterized by the development and increase of the mammals
heroic — Also, heroical. of, relating to, or characteristic of a hero or heroine.
mesozoic — 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.
Four-or-more syllable rhymes
paleozoic — noting or pertaining to an era occurring between 570 million and 230 million years ago, characterized by the advent of fish, insects, and reptiles.