hentai - although a hen compound, it merits a separate entry. Its classical meaning is "metamorphosis, transformation." It later came to mean "abnormality," and in modern colloquial Japanese is used almost exclusively to mean "pervert" or "perversion."

When a woman insults a man in anime, she generally uses on of three terms: hentai, sukebe, and etchi. Sukebe implies "oversexed" rather than "deviant." Etchi can be quite mild in some contexts, comparable to "lewd" or "Fresh!" These three terms are often used interchangeably, especially when someone is stringing together insults.

Though not as frequent, the word (o-)kama refers specifically to transvestitism and other gender-bending actions associated with homosexuality.