/ Dictionary / Index P Paleocene: Meaning and Definition of Find definitions for: Pa•le•o•cene Pronunciation: (pā'lē-u-sēn" or, esp. Brit., pal'ē-), [key] —adj. noting or pertaining to an epoch of the Tertiary Period, from 65 to 55 million years ago, and characterized by a proliferation of mammals. See table under —n. the Paleocene Epoch or Series. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: paleocene (Thesaurus) paleobotany paleoclimate Related Content Daily Word Quiz: prevalent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language