Glacial epoch

Noun	1.	glacial epoch - any period of time during which glaciers covered a large part of the earth's surface; "the most recent ice age was during the Pleistocene" Synonyms: glacial period, ice age
	2.	Glacial epoch - from two million to 11 thousand years ago; extensive glaciation of the northern hemisphere; the time of human evolution Synonyms: Pleistocene, Pleistocene epoch

geological period, glacial period, ice age, period, prehistoric culture, prehistory