English definition of “affair”
EVENTS [C] › a situation or set of related events, especially bad ones: The government's handling of the affair has been widely criticized.
RELATIONSHIP [C] › a sexual relationship between two people when one or both of them is married to someone else: He's been having an affair with a woman at work.
be sb's affair › If something is your affair, it is private and you do not want anyone else to be involved or know about it. → See also love affair