[ plahy-uh-seen ]
/ ˈplaɪ əˌsin /


noting or pertaining to an epoch of the Tertiary Period, occurring from 10 to 2 million years ago, and characterized by increased size and numbers of mammals, by the growth of mountains, and by global climatic cooling.


the Pliocene Epoch or Series.

Origin of Pliocene

First recorded in 1825–35; plio- + -cene


post-Pli·o·cene, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for pliocene

British Dictionary definitions for pliocene



/ (ˈplaɪəʊˌsiːn) /


of, denoting, or formed in the last epoch of the Tertiary period, which lasted for three million years, during which many modern mammals appeared


the Pliocene the Pliocene epoch or rock series

Word Origin for Pliocene

C19: plio- + -cene, from Greek kainos recent
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Science definitions for pliocene

[ plīə-sēn′ ]

The fifth and last epoch of the Tertiary Period, from about 5 to 2 million years ago. During this time the global climate became cooler and the number and expanse of grasslands and savannas increased greatly. This change in vegetation was accompanied by an increase in long-legged grazers. The land bridge between North America and South America also formed at this time, and massive ice sheets accumulated at the poles. In the later part of the epoch many of the species living in polar regions became extinct. See Chart at geologic time.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.