Noun | 1. | unlawful carnal knowledge - forbidden or tabu sexual intercourse between individuals carnal knowledge, copulation, sex act, sexual congress, sexual relation, relation, congress - the act of sexual procreation between a man and a woman; the man's penis is inserted into the woman's vagina and excited until orgasm and ejaculation occur extramarital sex, free love - sexual intercourse between individuals who are not married to one another |