Sexual sadism refers to paraphilia in which sexual gratification or sexual Arousal is obtained through or associated with inflicting pain or harm and humiliation on one's partner.
Individuals with Sexual sadism disorder have persistent fantasies in which sexual excitement results from inflicting psychological or physical suffering which include humiliation and terror on a sexual partner. This disorder is different from minor acts of aggression in normal sexual activity; for example, rough sex. In some cases, sexual sadists are able to find willing partners to participate in the sadistic activities.
Sexual sadism also involves illegal activities such as rape, torture, and even murder, in which case the death of the victim produces sexual excitement at its most extreme.
Rape may be an expression of Sexual sadism, however, it should be noted that the infliction of suffering is not the motive for most rapists, and the victim's pain and generally does not increase the rapist's sexual excitement. Rather, rape involves a combination of sex and gaining power over the victim. Both sexual sadist and rapist, need intensive psychiatric treatment and may be jailed for these activities.
Other /More definition:
sexual sadism refers to Paraphilia in which sexual arousal is associated with inflicting pain or humiliation.