. . . . "In the practice of medicine, especially surgery, and dentistry, anesthesia or anaesthesia (from Greek \u1F00\u03BD-, an-, \"without\"; and \u03B1\u1F34\u03C3\u03B8\u03B7\u03C3\u03B9\u03C2, aisth\u0113sis, \"sensation\"; see American and British English spelling differences) is an induced, temporary state with one or more of the following characteristics: analgesia (relief from or prevention of pain), paralysis (extreme muscle relaxation), amnesia (loss of memory), and unconsciousness. An anesthetic is an agent that causes anaesthesia."@en .