17.

black market
黑市

[雙語(yǔ)解釋]

A market place where illegal or hard-to-get items are sold or where money is illegal exchanged.
非法或緊俏物資的銷(xiāo)售點(diǎn)，或者非法換匯的地方。

例句：

Gangs are buying assault weapons on the black market.
黑幫總在黑市購(gòu)買(mǎi)攻擊性武器。