Main Entry: gla·cial

Pronunciation: \ˈglā-shəl\

Function: adjective

Etymology: Latin glacialis, from glacies

Date: 1656

1 : suggestive of ice: as a : extremely cold : frigid <a glacial wind> b : devoid of warmth and cordiality <a glacial handshake> c : coldly imperturbable <maintained a glacial calm>
2 : of a purity marked by the tendency to readily solidify in the form of ice-like crystals <glacial acetic acid>
3 a (1) : of, relating to, or being any of those parts of geologic time from Precambrian onward when a much larger portion of the earth was covered by glaciers than at present (2) capitalized : pleistocene b : of, relating to, or produced by glaciers c : suggestive of the very slow movement of glaciers <progress on the bill has been glacial>

— gla·cial·ly \-shə-lē\ adverb