Age of Mammals n 1: approximately the last 63 million years [syn: {Cenozoic}, {Cenozoic era}, {Age of Mammals}]
Mammal \Mam"mal\, n.; pl. {Mammals}. [L. mammalis belonging to the breast, fr. mamma the breast or pap: cf. F. mammal.] (Zool.) One of the Mammalia. [1913 Webster] {Age of mammals}. See under {Age}, n., 8. [1913 Webster]