peripheral

1 of 2

adjective

pe·​riph·​er·​al pə-ˈri-f(ə-)rəl 

1

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

2

a

: 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

peripherally adverb

peripheral

2 of 2

noun

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

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.

Synonyms

Adjective

• auxiliary
• additional
• accessory

Examples of peripheral in a Sentence

Adjective

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.

Recent Examples on the Web

Adjective

Once seen as a peripheral aspect of media, voiceover is increasingly being seen as a powerful and nuanced tool for shaping narratives, forging emotional bonds, and driving civic engagement. —Nia Bowers, USA Today, 11 July 2025

That can certainly be useful and may lead to cost efficiencies, but there are many peripheral AI use cases that do not turn startups into AI companies overnight. —Evan Renov, Forbes.com, 2 July 2025

Noun

Docking stations enhance productivity by connecting laptops to multiple peripherals with a single plug-in. —Ken Colburn, AZCentral.com, 7 July 2025

This deep $700 discount will easily cover the cost of a monitor and even some peripherals like a headset and mouse—whatever tickles your fancy. —Jade Chung-Lee, PC Magazine, 24 June 2025

Word History

First Known Use

Adjective

1808, in the meaning defined at sense 1

Noun

1966, in the meaning defined above

Phrases Containing peripheral

• peripheral nervous system
• peripheral neuropathy

Kids Definition

peripheral

1 of 2 adjective

pe·​riph·​er·​al pə-ˈrif-(ə-)rəl 

1

: of, relating to, located in, or forming a periphery

2

: auxiliary entry 1, supplementary

peripheral equipment

peripherally

-ē

adverb

peripheral

2 of 2 noun

: a device connected to a computer to provide communication (as input and output) or extra storage capacity

Medical Definition

peripheral

adjective

pe·​riph·​er·​al pə-ˈrif-(ə-)rəl 

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

peripherally

-ē 

adverb