freebooter

from WordNet (r) 3.0 (2006)

freebooter
    n 1: someone who takes spoils or plunder (as in war) [syn:
         {plunderer}, {pillager}, {looter}, {spoiler}, {despoiler},
         {raider}, {freebooter}]

from The Collaborative International Dictionary of English v.0.48

Freebooter \Free"boot`er\, n. [D. vrijbuiter, fr. vrijbuiten to
   plunder; vrij free + buit booty, akin to E. booty. See
   {Free}, and {Booty}, and cf. {Filibuster}.]
   One who plunders or pillages without the authority of
   national warfare; a member of a predatory band; a pillager; a
   buccaneer; a sea robber. --Bacon.
   [1913 Webster]

from The Devil's Dictionary (1881-1906)

FREEBOOTER, n.  A conqueror in a small way of business, whose
annexations lack of the sanctifying merit of magnitude.

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