Q: A “mistress” is a kept woman supported in secret by a married man who’s cheating on his wife. What do we call the man? My husband says a “lucky dog,” but he’s joking … I hope. Seriously, is there a word for this?
A: I’ve racked my brain, but can’t come up with a word for the cheating man. Perhaps “sugar daddy”? Of course that word is slanted, since it defines him in terms of the mistress but not the wife (he’s not a sugar daddy to the Mrs.).
“Gigolo” can describe a kept man, the masculine equivalent of the mistress. And “cuckold” is the masculine version of the wife who’s being cheated upon.
But as for the man who keeps a mistress, that’s perhaps a gap in the language that needs to be filled.
By the way, Cassell’s Dictionary of Slang says the expression “sugar daddy” (also know as “sugar,” “sugar papa,” “sugar pops,” and “sweet sugar”) originated in the US in the 1920s.
The earliest citation in the New York Times archive (from a 1926 drama review) refers to the vagaries of life in a traveling theater troupe, including the search for lodgings, the scarcity of hot water, and “the ‘sugar daddy’ of the show.”