| 1. | Also called glacial period, ice age. the geologically recent Pleistocene Epoch, during which much of the Northern Hemisphere was covered by great ice sheets. |
| 2. | any one of the Permian, Carboniferous, Cambrian, or Precambrian glaciations. |
| glacial period | |
noun | |
| 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" [syn: ice age] |