glaciation (n.)
1640s, "act of freezing," noun of action from past participle stem of Latin glaciare "to freeze," from glacies "ice" (probably from a suffixed form of PIE root *gel- "cold; to freeze"). Geological sense of "presence of a mass of ice covering a region" is from 1863.
)window.location='https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=byronic106@yahoo.com&lc=US&item_name=Donation+to +Help+Keep+Etymonline+Free+and+Open&no_note=0&cn=&curency_code=USD&bn=PP-DonationsBF:btn_donateCC_LG.gif:NonHosted'){kind=link}