[ plahy-stuh-seen ]
/ ˈplaɪ stəˌsin /


noting or pertaining to the epoch forming the earlier half of the Quaternary Period, beginning about two million years ago and ending 10,000 years ago, characterized by widespread glacial ice and the advent of modern humans.


the Pleistocene Epoch or Series.

Origin of Pleistocene

1830–40; < Greek pleîsto(s) most (superlative of polýs much) + -cene

Related forms

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

Examples from the Web for pleistocene

British Dictionary definitions for pleistocene


/ (ˈplaɪstəˌsiːn) /


of, denoting, or formed in the first epoch of the Quaternary period, which lasted for about 1 600 000 years. It was characterized by extensive glaciations of the N hemisphere and the evolutionary development of man


the Pleistocene the Pleistocene epoch or rock series

Word Origin for Pleistocene

C19: from Greek pleistos most + 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 pleistocene


[ plīstə-sēn′ ]

The earlier of the two epochs of the Quaternary Period, from about 2 million to 10,000 years ago. The Pleistocene Epoch was characterized by the formation of widespread glaciers in the Northern Hemisphere and by the appearance of humans. Mammals included both small forms, such as saber-toothed tigers and horses and giant ones, such as mammoths and mastodons. Almost all the giant mammals, including woolly mammoths, giant wolves, giant ground sloths, and massive wombats disappeared at the end of the Pleistocene and the start of the Holocene. See Chart at geologic time.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.