the joke’s on somebody
idiomPart ofjoke
the joke’s on somebody — idiom
1. Used to say that someone who tried to make another person look foolish now looks
1.idiom
Definition
Used to say that someone who tried to make another person look foolish now looks foolish instead.
Example
She tried to embarrass me, but the joke was on her.
Did you see that? The joke's on Tom for once.