Scaramouche

scaramouche \ˈskar-ə-ˌmüsh\ noun: 1. (capitalized) a stock character in the Italian commedia dell'arte that burlesques the Spanish don and is characterized by boastfulness and cowardliness, 2 a. a cowardly buffoon, b. rascal, scamp

Etymology: French Scaramouche, from Italian Scaramuccia, from scaramuccia skirmish

I never hear anyone use this word to call someone a coward or buffoon.