[pey-lee-uh-seen or, esp. British, pal-ee-]Geology
- noting or pertaining to an epoch of the Tertiary Period, from 65 to 55 million years ago, and characterized by a proliferation of mammals.
- the Paleocene Epoch or Series.
Origin of Paleocene
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for paleocene
The Oligocene division has been generally accepted as a distinct period, but “Paleocene” is not so widely used.
This collection was obviously of Torrejonian or middle Paleocene age.
The mammalian faunas of the Paleocene of central Utah, with notes on the geology.
Perhaps, this high ratio reflects the imperfectly carnivorous habits of the Paleocene creodonts as a group.
Word Origin and History for paleocene
Online Etymology Dictionary, © 2010 Douglas Harper
- The earliest epoch of the Tertiary Period, from about 65 to 58 million years ago. During this time, the Rocky Mountains formed and sea levels dropped, exposing dry land in North America, Australia, and Africa. Many new types of small mammals evolved and filled the niches left empty after the extinctions that ended the Cretaceous Period. Soft-bodied squid replaced the ammonites as the dominant form of mollusk. See Chart at geologic time.
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