What does "contraband" mean?

Additional senses

1. 2.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.] 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.
2. 3.Prohibited or excluded by law or treaty; forbidden; as, contraband goods, or trade. The contraband will always keep pace, in some measure, with the fair trade. Burke.
3. 4.To import illegaly, as prohibited goods; to smuggle. [Obs.] Johnson.
4. 5.To declare prohibited; to forbid. [Obs.] The law severly contrabands Our taking business of men's hands. Hudibras.