Amour

1. (n.) An illicit, secret or illegal love affair.

2. (n.) Love making; a love affair; usually, an unlawful connection in love; a love intrigue; an illicit love affair.

Thesaurus Entries

adulterous affair, adultery, affair, amorousness, cuckoldry, entanglement, eternal triangle, flirtation, forbidden love, hanky-panky, illicit love, infidelity, intimacy, intrigue, liaison, love, love affair, passion, relationship, romance, romantic tie, triangle, unfaithfulness