"Affair" is an odd word. In French "les affaires" are business (the business section of Air France is called "Affaires"
) and in English the real distinction lies in either attending to (a matter) or going to one (a celebration) or having one (a sexual relationship that sometimes illicit). Attending an affair is innocuous enough unless in the course of attending you meet someone with whom you have an affair. Then there is the meaning of the word which has to do with intrigue. The Profumo Affair
was a famous British scandal involving a member of parliament and "a model" (Christine Keeler), but affair didn't refer to the hanky panky necessarily, but to the compromising of the politician because of the fact that Keeler was sleeping with the Russian spy Yevgeny Ivanov (which sounds curiously similar to what Warren Buffett once said about derivatives, "It's not just whom you sleep with, but also whom they are sleeping with."
Similarly we might today speak of the Snowden affair. Using affair in connection with Snowden doesn't connote anything sexual and indeed it's unlikely that Snowden had much in the way of sex during the weeks when he inhabited the transit section of the Moscow airport--though Snowden might have fallen in love with someone en route between Hong Kong where he was staying and say Caracas or Quito which were two destinations he'd been heading towards before the Russians granted him temporary asylum. But how did affair come to be used in connection with sex outside of marriage? That's the question. The Free Dictionary
gives 8 definitions of affair and only the eighth ("A romantic and sexual relationship, sometimes one of brief duration, between two people who are not married to each other") has anything to do with sex.
This was originally posted to The Screaming Pope, Francis Levy's blog of rants and reactions to contemporary politics, art and culture}