processor An addressing mode found in many processors'

instruction sets where the instruction contains the address

of a memory location which contains the address of the operand

(the "effective address") or specifies a register which

contains the effective address. In the first case

(indirection via memory), accessing the operand requires two

memory accesses - one to fetch the effective address and

another to read or write the actual operand. Register

indirect addressing requires only one memory access.