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.
      [1913 Webster]

            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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The Collaborative International Dictionary of English v.0.48:

Contraband \Con"tra*band\, a.
   Prohibited or excluded by law or treaty; forbidden; as,
   contraband goods, or trade.
   [1913 Webster]

         The contraband will always keep pace, in some measure,
         with the fair trade.                     --Burke.
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The Collaborative International Dictionary of English v.0.48:

Contraband \Con"tra*band\, v. t.
   1. To import illegally, as prohibited goods; to smuggle.
      [Obs.] --Johnson.
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   2. To declare prohibited; to forbid. [Obs.]
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            The law severly contrabands
            Our taking business of men's hands.   --Hudibras.
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WordNet (r) 3.0 (2006):

contraband
    adj 1: distributed or sold illicitly; "the black economy pays no
           taxes" [syn: bootleg, black, black-market,
           contraband, smuggled]
    n 1: goods whose importation or exportation or possession is
         prohibited by law

Moby Thesaurus II by Grady Ward, 1.0:

116 Moby Thesaurus words for "contraband":
   Eighteenth Amendment, Prohibition Party, Volstead Act, actionable,
   against the law, anarchic, anarchistic, anomic, ban, banned,
   barred, black-market, bootleg, bootleg liquor, chargeable,
   cigarette smuggling, cigarettes, contrabandage, contrary to law,
   criminal, denial, disallowance, disapproved, dope, dope smuggling,
   drugs, embargo, excluded, exclusion, felonious, flawed, forbade,
   forbid, forbiddance, forbidden, forbidden fruit, forbidding,
   gunrunning, hot, hot goods, illegal, illegitimate, illicit,
   impermissible, index, index expurgatorius,
   index librorum prohibitorum, inhibition, injunction, interdict,
   interdiction, interdictum, irregular, jewel smuggling, jewels,
   justiciable, law, lawless, narcotics, narcotics smuggling, no-no,
   nonconstitutional, nonlegal, nonlicit, nonpermissible,
   not permitted, off limits, out of bounds, outlaw, outlawed,
   preclusion, prevention, prohibited, prohibition,
   prohibitory injunction, proscribed, proscription, punishable,
   refusal, rejection, repression, restrictive covenants, ruled out,
   ruling out, rumrunning, run, shut out, smuggled goods, smuggling,
   statute, stolen goods, sumptuary laws, suppression, taboo, tabooed,
   triable, unallowed, unauthorized, unconstitutional, under the ban,
   under-the-counter, under-the-table, unlawful, unlicensed,
   unofficial, unpermissible, unsanctioned, unstatutory, untouchable,
   unwarrantable, unwarranted, verboten, vetoed, wrongful, zoning,
   zoning laws



Bouvier's Law Dictionary, Revised 6th Ed (1856):

CONTRABAND, mar. law. Its most extensive sense, means all commerce which is
carried on contrary to the laws of the state. This term is also used to
designate all kinds of merchandise which are used, or transported, against
the interdictions published by a ban or solemn cry.
     2. The term is usually applied to that unlawful commerce which is so
carried on in time of war. Merlin, Repert. h.t. Commodities particularly
useful in war are contraband as arms, ammunition, horses, timber for ship
building, and every kind of naval stores. When articles come into use as
implements of war, which were before innocent, they may be declared to be
contraband. The greatest difficulty to decide what is contraband seems to
have occurred in the instance of provisions, which have not been held to be
universally contraband, though Vattel admits that they become so on certain
occasions, when there is an expectation of reducing an enemy by famine.
     3. In modern times one of the principal criteria adopted by the courts
for the decision of the question, whether any particular cargo of provisions
be confiscable as contraband, is to examine whether those provisions be in a
rude or manufactured state; for all articles, in such examinations, are
treated with greater indulgence in their natural condition than when wrought
tip for the convenience of the enemy's immediate use. Iron, unwrought, is
therefore treated with indulgence, though anchors, and other instruments
fabricated out of it, are directly contraband. 1 Rob. Rep. 1 89. See Vattel,
b. 3, c. 7 Chitty's L. of Nat. 120; Marsh. Ins. 78; 2 Bro. Civ., Law, 311; 1
Kent. Com. 135; 3 Id. 215.
     4. Contraband of war, is the act by which, in times of war, a neutral
vessel introduces, or attempts to introduce into the territory of, one of
the belligerent parties, arms, ammunition, or other effects intended for, or
which may serve, hostile operations. Merlin, Repert. h.t. 1 Kent, Com. 135;
Mann. Comm. B. 3, c. 7; 6 Mass. 102; 1 Wheat. 382; 1 Cowen, 56 John. Cas.
77, 120.