glaciation (n.)youdaoicibaDictYouDict[glaciation 词源字典]
1640s, "act of freezing," noun of action from past participle stem of Latin glaciare "to freeze," deom glacies "ice" (see glacial). Geological sense of "presence of a mass of ice covering a region" is from 1863.[glaciation etymology, glaciation origin, 英语词源]