also pre-glacial, "prior to the Ice Ages," 1853, from pre- + glacial.
Entries linking to preglacial
pre-
word-forming element meaning "before," from Old French pre- and Medieval Latin pre-, both from Latin prae (adverb and preposition) "before in time or place," from PIE *peri- (source also of Oscan prai, Umbrian pre, Sanskrit pare "thereupon," Greek parai "at," Gaulish are- "at, before," Lithuanian prie "at," Old Church Slavonic pri "at," Gothic faura, Old English fore "before"), extended form of root *per- (1) "forward," hence "beyond, in front of, before."
The Latin word was active in forming verbs. Also see prae-. Sometimes in Middle English muddled with words in pro- or per-.
glacial adj.
1650s, "cold, icy," from French glacial or directly from Latin glacialis "icy, frozen, full of ice," from glacies "ice," probably from a suffixed form of PIE root *gel- "cold; to freeze" (source also of Latin gelu "frost"). Geological sense "pertaining to glaciers" apparently was coined in 1846 by British naturalist Edward Forbes (1815-1854). Hence figurative sense "at an extremely slow rate," as of the advance of glaciers. Related: Glacially.