An amount the lender adds to an index to determine the interest rate on an adjustable rate mortgage.

Source: U.S. Department of Housing and Urban Development

The amount a lender adds to the index of an adjustable rate mortgage to establish an adjusted interest rate. For example, a margin of 1.50 added to a 7 percent index establishes an adjusted interest rate of 8.50 percent.

Source: Ginnie Mae

The amount of money or collateral deposited by a customer with his broker, by a broker with a clearing member, or by a clearing member with a clearing organization. The margin is not partial payment on a purchase. Also called Performance Bond. (1) Initial margin is the amount of margin required by the broker when a futures position is opened; (2) Maintenance margin is an amount that must be maintained on deposit at all times. If the equity in a customer's account drops to or below the level of maintenance margin because of adverse price movement, the broker must issue a margin call to restore the customer's equity to the initial level. See Variation Margin. Exchanges specify levels of initial margin and maintenance margin for each futures contract, but Futures Commission Merchants may require their customers to post margin at higher levels than those specified by the exchange. Futures margin is determined by the SPAN margining system, which takes into account all positions in a customer’s portfolio.

Source: Commodity Futures Trading Commission