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Paleocene

[ pey-lee-uh-seen or, especially British, pal-ee- ]
/ ˈpeɪ li əˌsin or, especially British, ˈpæl i- /
Geology
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adjective
noting or pertaining to an epoch of the Tertiary Period, from 65 to 55 million years ago, and characterized by a proliferation of mammals.
noun
the Paleocene Epoch or Series.
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Origin of Paleocene

First recorded in 1875–80; paleo- + -cene
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use Paleocene in a sentence

Scientific definitions for Paleocene

Paleocene
[ pālē-ə-sēn′ ]

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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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