|a.||1.||Of or pertaining to a periphery; constituting a periphery; peripheric.|
|2.||(Anat.) External; away from the center; |
|Noun||1.||peripheral - (computer science) electronic equipment connected by cable to the CPU of a computer; "disk drives and printers are important peripherals"|
|Adj.||1.||peripheral - on or near an edge or constituting an outer boundary; the outer area; "Russia's peripheral provinces"; "peripheral suburbs"|
central - in or near a center or constituting a center; the inner area; "a central position"; "central heating and air conditioning"
|2.||peripheral - related to the key issue but not of central importance; "a peripheral interest"; "energy is far from a peripheral issue in the economy"; "peripheral issues"|
|(hardware)||peripheral - (Or "peripheral device", "device") Any part of a
computer other than the CPU or working memory,
i.e. disks, keyboards, monitors, mice, printers,
scanners, tape drives, microphones, speakers,
cameras, to list just the less exotic ones.|
High speed working memory, such as RAM, ROM or, in the old days, core would not normally be referred to as peripherals. The more modern term "device" is also more general in that it is used for things such as a pseudo-tty, a RAM drive, or a network adaptor.
Some argue that, since the advent of the personal computer, the motherboard, hard disk, keyboard, mouse, and monitor are all parts of the base system, and only use the term "peripheral" for optional additional components.