The Collaborative International Dictionary of English v.0.48:

Bravo \Bra"vo\, n.; pl. Bravoes. [I. See Brave, a.]
   A daring villain; a bandit; one who sets law at defiance; a
   professional assassin or murderer.
   [1913 Webster]

         Safe from detection, seize the unwary prey.
         And stab, like bravoes, all who come this way.
                                                  --Churchill.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Bravo \Bra"vo\, interj. [It. See Brave.]
   Well done! excellent! an exclamation expressive of applause.
   [1913 Webster]

WordNet (r) 3.0 (2006):

bravo
    n 1: a murderer (especially one who kills a prominent political
         figure) who kills by a surprise attack and often is hired
         to do the deed; "his assassins were hunted down like
         animals"; "assassinators of kings and emperors" [syn:
         assassin, assassinator, bravo]
    2: a cry of approval as from an audience at the end of great
       performance
    v 1: applaud with shouts of `bravo' or `brava'