margin,n. 1. A boundary or edge. 2. A measure or degree of difference. 3.PROFIT MARGIN. 4. The difference between a loan’s face value and the market value of the collateral that secures the loan. 5. Cash or collateral required to be paid to a securities broker by an investor to protect the broker against losses from securities bought on credit. [Cases: Securities Regulation 45.10, 45.11. C.J.S. Securities Regulation § 117.] 6. The amount of an investor’s equity in securities bought on credit through the broker. — margin,vb. — marginal, margined,adj.

good-faith margin.The amount of margin that a creditor exercising good judgment would customarily require for a specified security position. • This amount is established without regard to the customer’s other assets or securities positions held with respect to unrelated transactions.

[Blacks Law 8th]