Webster's Revised Unabridged Dictionary · 1913

black market

black market , noun

1.
the illicit buying and selling of goods, in violation of price controls, rationing, tax laws, prohibition of sale, etc.
2.
a place where such illegal commerce is conducted, or the entire system of such illicit commerce considered as a whole; as, the black market accounts for twenty percent of the Ukrainian economy.

black-market , adjective

distributed or sold illicitly.