Pervert

Perversion is a type of human behavior that deviates from that which is understood to be orthodox or normal. Although the term perversion can refer to a variety of forms of deviation, it is most often used to describe sexual behaviors that are considered particularly abnormal, repulsive or obsessive. Perversion differs from deviant behavior, in that the latter covers areas of behavior (such as petty crime) for which perversion would be too strong a term. It is often considered derogatory, and, in psychological literature, the term paraphilia has been used as a replacement, though this term is controversial, and deviation is sometimes used in its place.

One view is that the concept of perversion is subjective, and its application varies depending on the individual. Another view considers that perversion is a degradation of an objectively true morality. Originating in the 1660s a pervert was originally defined as "one who has forsaken a doctrine or system regarded as true, apostate." The sense of a pervert as a sexual term was derived in 1896, and applied originally to variants of sexualities or sexual behavior believed harmful by the individual or group using the term.

The verb pervert is less narrow in reference than the related nouns, and can be used without any sexual connotations. It is used in English law for the crime of perverting the course of justice which is a common law offence. There is a transition to the sexual in 'the technique of purposeful perversion' of conversational remarks: "Purposeful perversion of what a woman has said ... is a long step closer to a direct attempt at seduction or rape."

The noun sometimes occurs in abbreviated slang form as "perv" and used as a verb meaning "to act like a pervert", and the adjective "pervy" also occurs. All are often, but not exclusively, used non-seriously.

In economics the term "perverse incentive" means a policy that results in an effect contrary to the policymakers' intention.

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