劍橋詞典

an unofficial but not completely illegal system in which products are bought and sold
（非正式但并不完全非法的）灰色市場
The store sells designer clothes and shoes sourced from the grey market . 這家商店出售從灰色市場進(jìn)貨的名牌服裝和鞋子。
比較
black market

buying and selling of a company's shares before they are available officially
（在公司股票尚未正式發(fā)放時進(jìn)行交易的）股票灰色市場，暗盤市場
First dealings in the company's shares will start on the grey market on 27 March and formal trading begins on 2 April . 這家公司的股票將于3月27日開始進(jìn)入暗盤市場，然后在4月2日正式上市交易。

people over about 50, considered as a group to which products can be sold
針對50歲以上人群的市場，白發(fā)市場
Motorbike manufacturers are selling to the grey market as much as to younger people . 摩托車制造商們賣給白發(fā)市場的摩托車和賣給年輕人的一樣多。 返回 the grey market