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

While an opioid would’ve been an easy choice, a doctor performed a nerve block instead, numbing the peripheral areas of pain rather than sedating the brain. —Dr. Sanjay Gupta, CNN Money, 2 Sep. 2025

No life can be truly assessed from any but a peripheral vision. —Diana Lodderhose, Deadline, 29 Aug. 2025

Noun

When supported, Sony’s advanced haptic feedback and adaptive triggers add so much immersion, although since using Nintendo’s Switch 2 Pro Controller, there might be a new champion amongst my go-to peripherals. —Mitch Wallace, Forbes.com, 4 Sep. 2025

On the right are two more USB Type-A ports, giving you plenty of connectivity for ordinary peripherals. —Brian Westover, PC Magazine, 25 Aug. 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