Definitions for "Index register"
(computer science) a register used to determine the address of an operand
Also known as , IX or by other names. The register used to hold a value that becomes a factor in an indexed addressing mode. Frequently used for arithmetic operations, though without as many capabilities as an accumulator.
a specialpurpose register used by a processor when performing indexed addressing. The value in the index register is usually the reference location to which a displacement will be added.