analgesia (n.)youdaoicibaDictYouDict[analgesia 词源字典]
"absence of pain," 1706, medical Latin, from Greek analgesia "painlessness, insensibility," from analgetos "without pain, insensible to pain" (also "unfeeling, ruthless"), from an- "not" (see an- (1)) + algein "to feel pain" (see -algia).[analgesia etymology, analgesia origin, 英语词源]