Adultery :  (noun)

1: extramarital sex that willfully and maliciously interferes with marriage relations; "adultery is often cited as grounds for divorce" [syn: criminal conversation, fornication]

act of love, adulterous affair, affair, amour, aphrodisia, ass, balling, carnal knowledge, climax, cohabitation, coition, coitus, coitus interruptus, commerce, concubinage, congress, connection, copula, copulation, coupling, criminal conversation, cuckoldry, diddling, entanglement, eternal triangle, extracurricular sex, extramarital relations, flirtation, forbidden love, fornication, free love, free-lovism, hanky-panky, illicit love, incest, infidelity, intercourse, intimacy, intrigue, liaison, love affair, lovemaking, making it with, marital relations, marriage act, mating, meat, onanism, orgasm, ovum, pareunia, premarital relations, premarital sex, procreation, relations, romance, romantic tie, screwing, sex, sex act, sexual climax, sexual commerce, sexual congress, sexual intercourse, sexual relations, sexual union, sleeping with, sperm, triangle, unfaithfulness, venery,