The Collaborative International Dictionary of English v.0.48:

Contraband \Con"tra*band\, n. [It. contrabando; contra + bando
   ban, proclamation: cf. F. contrebande. See Ban an edict.]
   1. Illegal or prohibited traffic.
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            Persons the most bound in duty to prevent
            contraband, and the most interested in the seizures.
                                                  --Burke.
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   2. Goods or merchandise the importation or exportation of
      which is forbidden.
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   3. A negro slave, during the Civil War, escaped to, or was
      brought within, the Union lines. Such slave was considered
      contraband of war. [U.S.]
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   Contraband of war, that which, according to international
      law, cannot be supplied to a hostile belligerent except at
      the risk of seizure and condemnation by the aggrieved
      belligerent. --Wharton.
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