grey market
noun🔊/ˌɡreɪ ˈmɑːkɪt/
🔊/ˌɡreɪ ˈmɑːrkɪt/
(US English usually gray market)
[usually singular]a system in which products are imported into a country and sold without the permission of the company that produced them 灰市，水货市场（未经生产公司授权而进口并销售其产品） - (British English)
old people, when they are thought of as customers for goods （统称）老年顾客，老年客户