the grey market
noun [ S ]
UK (US the gray market) ukus COMMERCE
an unofficial but not illegal system of selling goods:
The store sells designer clothes and shoes sourced from the grey market .
Compare
black market
FINANCE
the buying and selling of a company's shares before they are available officially:
First dealings in the company's shares will start on the grey market on March 27 and formal trading begins on April 2.
MARKETING
people over about 50, considered as a group to which products can be sold:
Motorbike manufacturers are selling to the grey market as much as to younger people.