Of, belonging to, or designating the age of geologic time that includes the Triassic, Jurassic, and Cretaceous times and is characterized by the introduction of flying reptiles, wild birds, and flowering flowers and by the looks and extinction of dinosaurs. See dining table at geologic time.
Of a geologic period within the Phanerozoic eon that comprises the Triassic, Jurassic and Cretaceous periods from about 230 to 65 million years back, whenever life on earth had been dominated by reptiles.
Belonging, or relating, on secondary or reptilian age, or perhaps the age involving the Paleozoic and Cenozoic. See Chart of geology.
of or associated with or denoting the Mesozoic era