languor (n.)youdaoicibaDictYouDict[languor 词源字典]
c. 1300, "disease, distress, mental suffering," from Old French langor "sickness, weakness" (Modern French langueur), from Latin languorem (nominative languor) "faintness, feebleness, lassitude," from languere "be weak or faint" (see lax). Sense shifted to "faintness, weariness" (1650s) and "habitual want of energy" (1825).[languor etymology, languor origin, 英语词源]