sadism

n. 1. The desire to inflict and practice of inflicting pain and humiliation on another as a way of gaining sexual arousal and pleasure derived from the marquis de Sade, who wrote on this subject in the late 1700s and early 1800s. 2. Enjoyment of inflicting pain in nonsexual contexts as in police beating handcuffed prisoners or teachers humiliating students. 3. In psychoanalysis, which views all pleasure as sexual, any form of aggressiveness, or expression of Thanatos, the death instinct, such as an infant's biting the nipple, is seen as sadistic.