The Collaborative International Dictionary
Glacial \Gla"cial\, a. [L. glacialis, from glacies ice: cf. F. glacial.]
Pertaining to ice or to its action; consisting of ice; frozen; icy; esp., pertaining to glaciers; as, glacial phenomena.
--Lyell.-
(Chem.) Resembling ice; having the appearance and consistency of ice; -- said of certain solid compounds; as, glacial phosphoric or acetic acids.
Glacial acid (Chem.), an acid of such strength or purity as to crystallize at an ordinary temperature, in an icelike form; as acetic or carbolic acid.
Glacial drift (Geol.), earth and rocks which have been transported by moving ice, land ice, or icebergs; bowlder drift.
Glacial epoch or Glacial period (Geol.), a period during which the climate of the modern temperate regions was polar, and ice covered large portions of the northern hemisphere to the mountain tops.
Glacial theory or Glacial hypothesis. (Geol.) See Glacier theory, under Glacier.
WordNet
n. 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, glacial epoch]
Wikipedia
A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate between glacial periods. The last glacial period ended about 15,000 years ago. The Holocene epoch is the current interglacial. A time when there are no glaciers on Earth is considered a greenhouse climate state.
Usage examples of "glacial period".
They are excellent geological specimens of deeply bored, striated cavities formed in the glacial period by the grinding action of the lower gravel surface of the massive continental ice sheet that covered the northeastern part of North America between 30,000 and 50,000 years ago.
Somewhere, not impossibly, the conditions causing the glacial period still obtain and Virginia is buried under a mass of snow.
But within a few shar's of their landing, the glacial period was giving way to a warmer and rainier climate (circa 430,000 years ago).
The absence of lakes also showed them that there had been no Glacial period, in the latitudes they were crossing, for a very long time.
This is most important in its bearing on our theory, as indicating that they radiated from a common centre 'after the Glacial Period'.
And so the glacial period, which had threatened to destroy the human race, became its greatest teacher because it forced man to use his brain.