1. amusingly unconventional and idiosyncratic:"his zany humour"
noun
1. a zany person.
▪ a comic performer partnering a clown, whom he imitated in an amusing way.
Word Originlate 16th century: from French zani or Italian zan(n)i, Venetian form of Gianni, Giovanni ‘John’, stock name of the servants acting as clowns in the commedia dell'arte.