margin account

In finance, a margin is collateral that the holder of a position in securities, options, or futures contracts has to deposit to cover the credit risk of his counterparty. This risk can arise if the holder has done any of the following:borrowed cash from the counterparty to buy securities or options,sold securities or options short, orentered into a futures contract. The collateral can be in the form of cash or securities, and it is deposited in a margin account. On U.S. futures exchanges, margin is formally called performance bond.
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Noun
1. an account with a securities brokerage in which the broker extends credit
(antonym) cash account
(hypernym) brokerage account

A leverageable account in which stocks can be purchased for a combination of cash and a loan. The loan in the margin account is collateralized by the stock and, if the value of the stock drops sufficiently, the owner will be asked to either put in more cash, or sell a portion of the stock. Margin rules are federally regulated, but margin requirements and interest may vary among broker/dealers.