the black market

     "The black market" means the illicit or illegal sale of goods that are usually only sold by the government, or through government regulation. Things that are illegal to possess, such as narcotics or stolen goods, are not generally included in the category of black market goods. An example for an American is a bit hard to think of. Liquor during prohibition made a black market. You could get it legally from a drugstore, but only if you had a prescription. You could buy liquor on the black market, though--or from a bootlegger. The bootlegger might have illegally imported the liquor, or he might have made it himself. Rationed goods ( each person is only allowed one or a few ) are sometimes resold on the black market.  Something that could only be purchased by a member of a certain group--a sports team, for instance--might find its way to the black market, because it couldn't really be resold in a store or through an ad. Sales are made by word of mouth ( each person who hears about the sale tells other people ) or in person.