3. zany a secondary character in old comedies, usu. a bungling imitator, derived from the maleservant figures of commedia dell'arte.
4. zany a buffoon; clown.
Etymology: (1560–70; (< MF) < It zan(n)i a servant character in the commedia dell'arte, perh. orig. the character's name, Gianni, for Giovanni John)
Definition of 'zany'
Princeton's WordNet
1. (noun)zany a buffoon in one of the old comedies; imitates others for ludicrous effect
2. (adj)fathead, goof, goofball, bozo, jackass, goose, cuckoo, twat, zany a man who is a stupidincompetentfool
3. (adj)cockamamie, cockamamy, goofy, sappy, silly, wacky, whacky, zany ludicrous, foolish "gave me a cockamamie reason for not going"; "wore a goofy hat"; "a silly idea"; "some wacky plan for selling more books"
4. (adj)buffoonish, clownish, clownlike, zany like a clown "a buffoonish walk"; "a clownish face"; "a zany sense of humor"
Definitions of zany 
