contraband (n.)

1520s, "smuggling, illegal or prohibited traffic;" 1590s, "smuggled goods, anything by law forbidden to be imported or exported;" from Middle French contrebande "a smuggling," from older Italian contrabando (modern contrabbando) "unlawful dealing," etymologically "contrary to proclamation," from Latin contra "against" (see contra (prep., adv.)) + Medieval Latin bannum, from Frankish *ban "a command" or some other Germanic source (see ban (v.)).  As an adjective, "prohibited by law, proclamation, or treaty," 1650s.