computer peripheral

For an account of the words periphery and peripheral as they are used in biology, sociology, politics, computer hardware, and other fields, see the periphery disambiguation page. A peripheral is a piece of computer hardware that is added to a host computer ,i.e any hardware except the computer, in order to expand its abilities. More specifically, the term is used to describe those devices that are optional in nature, as opposed to hardware that is either demanded or always required in principle.
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Noun
1. (computer science) electronic equipment connected by cable to the CPU of a computer; "disk drives and printers are important peripherals"
(synonym) peripheral, peripheral device
(hypernym) electronic equipment
(hyponym) printer
(part-holonym) computer, computing machine, computing device, data processor, electronic computer, information processing system
(classification) computer science, computing

See peripheral equipment.