Meaning

noun a buffoon in one of the old comedies; imitates others for ludicrous effect

noun a man who is a stupid incompetent fool

adjective ludicrous, foolish

originFrom Middle French zani, zanni, from Italian zanni (“a kind of masked clown character”), from Zanni, a Venetian form of Giovanni. Doublet of Zanni, John, and Giovanni.

Etymology from Wiktionary, CC BY-SA 3.0