pe·​riph·​er·​al | \pə-ˈri-f(ə-)rəl \

Definition of peripheral 

(Entry 1 of 2)

1 : of, relating to, involving, or forming a periphery or surface part

2a : of, relating to, affecting, or being part of the peripheral nervous system peripheral nerves peripheral neuritis

b : of, relating to, or being blood in the systemic circulation peripheral lymphocytes

3 : of, relating to, or being the outer part of the field of vision good peripheral vision

4 : auxiliary, supplementary peripheral equipment also : of or relating to computer peripherals



Definition of peripheral (Entry 2 of 2)

: a device connected to a computer to provide communication (such as input and output) or auxiliary functions (such as additional storage)

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Other Words from peripheral


peripherally adverb

Synonyms & Antonyms for peripheral

Synonyms: Adjective

accessorial, accessory, appurtenant, auxiliary, supplemental, supplementary

Antonyms: Adjective

chief, main, principal

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Did You Know?

Your peripheral vision is the outer area of your field of vision, where you can still detect movement and shapes. It can be very valuable when, for instance, you're driving into Chicago at rush hour, especially when switching lanes. When people call an issue in a discussion peripheral, they mean that it's not of primary importance, and they're probably suggesting that everyone get back to the main topic. Peripheral is now also a noun: computer peripherals are the added components—printers, webcams, microphones, etc.—that increase a computer's capacities.

Examples of peripheral in a Sentence


If we focus too much on peripheral issues, we will lose sight of the goal. peripheral devices such as modems and scanners He saw in his peripheral vision that a car was trying to pass him.
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Recent Examples on the Web: Adjective

With diabetes, people traditionally worry about the eyes, the peripheral nerves, the kidneys, but the liver doesn’t receive the same sort of attention, Harrison said. Cathie Anderson, sacbee, "A liver disease you've never heard of is putting 12 million Americans' lives at risk," 7 June 2018 The American drug dealers are largely peripheral figures here, and all the more damnable for their absence. Justin Chang,, "Cannes kicks off with two Spanish-language dramas, 'Everybody Knows' and 'Birds of Passage'," 9 May 2018 The adjustable hood cinched up snug and kept rain from trickling in while still providing enough peripheral vision to navigate the park’s tight, marshy channels. Outside Online, "The Best Summer Jackets of 2018," 15 May 2018 The fact that even Ant-Man, a fairly peripheral character in the Marvel universe, could front an instant box-office smash is a testament to the studio’s lasting appeal. Andrew R. Chow, New York Times, "‘Ant-Man and the Wasp’ Is Marvel’s 20th Box-Office No. 1 in a Row," 8 July 2018 Other than his batting average — and the results that have come from it — Schoop’s peripheral statistics aren’t extremely different from last season. Eduardo A. Encina,, "Orioles' Jonathan Schoop searches for form at the plate that made him an All-Star a year ago," 7 July 2018 His peripheral numbers are less exciting: Floro has struck out 6.7 batters per nine innings while walking three batters per nine. Andy Mccullough,, "Dodgers acquire Cincinnati reliever Dylan Floro to bolster bullpen," 4 July 2018 Until the Bears find long-term stability in the kicking game, Gould’s ongoing success always will be in the peripheral vision of Bears fans and critics. Dan Wiederer,, "Will Pat O'Donnell respond to competition in fight to stick with Bears?," 13 July 2018 There's a lot of peripheral things that happen off of one thing. Jon Meoli,, "Orioles sit Trey Mancini in effort to reverse young slugger's season-long struggles," 11 July 2018

Recent Examples on the Web: Noun

On top of that, many new peripherals are still using the old connections. Valentina Palladino, Ars Technica, "Guidemaster: Picking the right Thunderbolt 3 or USB-C dock for your desk," 3 July 2018 That gives it the same precision as the Microsoft Surface Precision Mouse, Microsoft's other recent peripheral. Mark Hachman, PCWorld, "Microsoft's Classic Intellimouse updates 2003's iconic mouse for the modern era," 27 June 2018 Violet kept them in her peripherals. 2 Bo was hiding behind a powerjack, only meters from the fire door and the emergency exit sign glowing above it through the gloom. Andrew Liptak, The Verge, "A transgender girl rises up against alien invaders in Rich Larson’s novel Annex," 8 July 2018 Strong sales momentum has analysts forecasting double-digit earnings growth for firms in the semiconductor, internet software & services, technology hardware, storage & peripherals and IT services industries. Michael Wursthorn, WSJ, "With Stock Market in Lull, Investors Pin Hopes on Earnings Boom," 10 July 2018 What’s unclear is whether Microsoft is providing the dongle as a sop to those who are investing in the USB-C interface and peripherals, or whether Microsoft sees USB-C as a true replacement for the Surface Connector. Mark Hachman, PCWorld, "Microsoft's $80 Surface USB-C dongle suggests there'll be no new Surface Dock," 25 June 2018 When that moment comes, perhaps USB-C peripherals and cables will have fallen in price and complexity to the point where each wireless pair of headphones will have USB-C as its fallback connection. Vlad Savov, The Verge, "Why USB-C headphones aren’t, and likely never will be, mainstream," 15 June 2018 As the above gallery shows, the XAC can be connected to a variety of peripherals, most of which offer binary on/off input—like a basic button press. Sam Machkovech, Ars Technica, "In the lab with Xbox’s new Adaptive Controller, which may change gaming forever," 17 May 2018 Yet Steam Link became the more viable element of the platform once Valve ditched the hardware peripheral and made the software available for smart TVs. Nick Statt, The Verge, "Valve’s PC game streaming service Steam Link launches in beta on Android," 17 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'peripheral.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of peripheral


1808, in the meaning defined at sense 1


1966, in the meaning defined above

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Statistics for peripheral

Last Updated

26 Oct 2018

Look-up Popularity

Time Traveler for peripheral

The first known use of peripheral was in 1808

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More Definitions for peripheral



English Language Learners Definition of peripheral

 (Entry 1 of 2)

: not relating to the main or most important part

computers : connected to a computer but not an essential part of it

: of or relating to the area that is to the side of the area you are looking at



English Language Learners Definition of peripheral (Entry 2 of 2)

computers : a piece of equipment (such as a printer, speaker, etc.) that is connected to a computer but is not an essential part of it


pe·​riph·​er·​al | \pə-ˈrif-(ə-)rəl \

Medical Definition of peripheral 

1 : of, relating to, involving, forming, or located near a periphery or surface part (as of the body)

2 : of, relating to, affecting, or being part of the peripheral nervous system peripheral nerves

3 : of, relating to, or being the outer part of the visual field good peripheral vision

4 : of, relating to, or being blood in the systemic circulation peripheral lymphocytes peripheral blood

Other Words from peripheral

peripherally \ -​ē \ adverb

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Comments on peripheral

What made you want to look up peripheral? Please tell us where you read or heard it (including the quote, if possible).


to clear from alleged fault or guilt

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