Noun
A group of businesses that offer products that are related from a consumer's perspective but which have no institutional connections.
A market that trades in the medium of exchange of a lower-level market, such as money, derivatives, or credit.
A market that trades in access to audiences or consumers.
The social and political infrastructure within which a market functions.
The process of promoting the exchange or adoption of things other than goods or services that are offered for sale.
Source: en.wiktionary.org