the.com/anesthetic

means A substance that blocks pain or knocks out sensation entirely, so your body can be operated on without you feeling (or sometimes witnessing) a thing.

from From Greek 'anaisthesia' — 'an-' (without) plus 'aisthesis' (sensation, feeling), the same root that gives us 'aesthetic.' So aesthetics and anesthetics are etymological siblings: one is about heightened feeling, the other about its total absence. The English word was popularized in the 1840s, right as ether and chloroform were turning surgery from a scream-filled ordeal into something survivable — a word coined for an era that finally figured out how to make the knife bearable.