[sometimesp-] designating or of the first geologic period of the Cenozoic Era, subdivided into the Paleocene, Eocene, and Oligocene epochs: formerly a subdivision of the Tertiary Period
Origin of Paleogenefrom paleo- + Classical Greek -gen?s, born: see -gen
the Paleogene Period or its rocks
The oldest of two subdivisions of the Tertiary Period, from about 66 to about 23 million years ago, and including the Paleocene, Eocene, and Oligocene Epochs.
Origin of PaleogeneGerman Paläogen paläo- paleo- -gen -gene