- anesthesia (n.)
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- 1721, "loss of feeling," Modern Latin, from Greek anaisthesia "want of feeling, lack of sensation (to pleasure or pain)," from an- "without" (see an- (1)) + aisthesis "feeling," from PIE root *au- "to perceive" (see audience). With abstract noun ending -ia. As "a procedure for the prevention of pain in surgical operations," from 1846.