I've often misheard the lyrics to the Cole Porter tune "One of those things."
It has been an odd misunderstanding, hardly worth calling a mondegren. I in fact developed an elaborate theory about how the words that I heard or THOUGHT I heard, words that didn't make a lot of sense, came to be.
I thought the lyrics, as least when sung by female vocalists such as Anita O'Day, included the phrase "Goodbye dear lay-men."
Why would she say "lay-men"? Because the song is addressed to non-professionals??
Why, indeed. The lyrics are addressed to a specific person of the opposite sex, so the term there shouldn't be plural in any event.
I had a goofy theory, which was that Porter had written it for a man to sing, and had written "Goodbye dear ladies." When a lady is singing, she turns it (according to this bad logic) into "goodbye dear lay-men."
Pretty dumb, as I say.
Only recently did I check on any of this. The line reads, "So good bye dear, and amen, here's hoping we meet now and then."