BROKER

n. middleman, intermediary; stockbroker; agent who buys and sells property for others

v. act as a broker or middleman; buy and sell property for others

In commerce, a broker is a party that mediates between a buyer and a seller. A broker who also acts as a seller or as a buyer becomes a party to the deal. Distinguish agent: one who acts on behalf of a principal. A brokerage or a brokerage firm is a business that acts as a broker. A sales person working for a securities or commodity brokerage firm is popularly (but incorrectly) called a "broker." A broker in that context is, strictly speaking, an exchange member who actually executes the purchase or sale order in the pit, on the exchange, as a service to the client of the firm for which that salesman works.
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Noun
1. a businessman who buys or sells for another in exchange for a commission
(synonym) agent, factor
(hypernym) businessperson, bourgeois
(hyponym) auctioneer
(member-holonym) brokerage, brokerage firm, securities firm
Verb
1. act as a broker
(hypernym) negociate, negotiate, talk terms
(derivation) brokerage
(classification) commerce, commercialism, mercantilism

n. broker, stockbroker; agent who buys and sells property for others

n. exchange broker, financial agent or intermediary dealing with the stock market, stock exchange broker, one who deals with the trading of stocks in the stock market