The Collaborative International Dictionary of English v.0.48:

Swashbuckler \Swash"buc`kler\, n.
   A bully or braggadocio; a swaggering, boastful fellow; a
   swaggerer. --Milton.
   [1913 Webster]

WordNet (r) 3.0 (2006):

swashbuckler
    n 1: a reckless impetuous irresponsible person [syn:
         daredevil, madcap, hothead, swashbuckler,
         lunatic, harum-scarum]

Moby Thesaurus II by Grady Ward, 1.0:

76 Moby Thesaurus words for "swashbuckler":
   Herod, battler, belligerent, belted knight, bickerer, blade,
   blatherskite, bluff, bluffer, blusterer, braggart, bravo, brawler,
   bucko, bully, bullyboy, combatant, competitor, contender,
   contestant, disputant, duelist, enforcer, fanfaron, fencer, feuder,
   fighter, fighting cock, foilsman, gamecock, gladiator, goon,
   gorilla, hatchet man, hector, hectorer, hood, hoodlum, hooligan,
   jouster, knight, miles gloriosus, militant, peacock, plug-ugly,
   quarreler, ranter, raver, rioter, rival, roisterer, rough, rowdy,
   ruffian, sabreur, scrapper, scuffler, squabbler, strong arm,
   strong-arm man, strong-armer, struggler, strutter, swaggerer,
   swanker, swash, swasher, sword, swordplayer, swordsman, thug,
   tilter, tough, tussler, vaporer, wrangler