John's no fool. He's never going to believe that excuse.
(redirected from be nobody's fool)
be no fool
To be worldly and difficult to trick or deceive. Your teacher is no fool—she'll never believe that your homework blew away on your walk home from school.
be no (or nobody's) fool
be a shrewd or prudent person.
be ˌno/ˌnobody’s ˈfool
be a clever person who cannot easily be tricked or cheated by anyone: You won’t be able to cheat her — she’s nobody’s fool.Don’t underestimate him. He’s no fool.