The Collaborative International Dictionary of English v.0.48:

Bandit \Ban"dit\ (b[a^]n"d[i^]t), n.; pl. Bandits
   (b[a^]n"d[i^]ts), or Banditti (b[a^]n*d[i^]t"t[i^]). [It.
   bandito outlaw, p. p. of bandire to proclaim, to banish, to
   proscribe, LL. bandire, bannire. See Ban an edict, and cf.
   Banish.]
   An outlaw; a brigand.
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         No savage fierce, bandit, or mountaineer. --Milton.
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   Note: The plural banditti was formerly used as a collective
         noun.
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               Deerstealers are ever a desperate banditti. --Sir
                                                  W. Scott.
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