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glacial epoch

noun

Also called glacial period, ice age. the geologically recent Pleistocene Epoch, during which much of the Northern Hemisphere was covered by great ice sheets.
any one of the Permian, Carboniferous, Cambrian, or Precambrian glaciations.

Origin of glacial epoch

First recorded in 1840–50
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for glacial period

glacial period

noun

any period of time during which a large part of the earth's surface was covered with ice, due to the advance of glaciers, as in the late Carboniferous period, and during most of the Pleistocene; glaciation
(often capitals) the Pleistocene epoch
Brit equivalent: glacial epoch, ice age
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