APA Dictionary of Psychology

stimulation of the genitalia by the mouth or tongue. The activity may be performed by heterosexual or homosexual couples, either as a precoital form of stimulation or carried to orgasm. Application of the mouth to the male genitalia is called fellatio; application of the mouth to the female genitalia is known as cunnilingus. Also called buccal intercourse; oral–genital contact. See also oral sex.