peripheral: Meaning and Definition of

pe•riph•er•al

1. pertaining to, situated in, or constituting the periphery: peripheral resistance on the outskirts of the battle area.
2. concerned with relatively minor, irrelevant, or superficial aspects of the subject in question.
3. near the surface or outside of; external.
4. of or pertaining to a peripheral.

1. a device or unit that operates separately from the CPU but is connected to it, as a magnetic disk or tape unit or a printer.