Mike was visiting Jim and discussing Jim's problems with his wife when Jim's doorbell rang.
Jim answered the door and was handed a paper, which the deliverer said was a subpoena.
Jim showed it to Mike and asked him if he knew what it was.
Mike in his pompous lack of knowledge said,
"Of course I know what a subpoena is."
"Well, what exactly is it?" Jim asked.
"Well," said Mike, "that's legal talk. Your wife is suing you for divorce.
We know that 'sub' means 'under' and 'poena' is Latin for 'penis', so --
'subpoena' means under the penis --
which means she's got you by the balls."