periphery

noun

pe·​riph·​ery pə-ˈri-f(ə-)rē 

plural peripheries

1

: the perimeter of a circle or other closed curve

also : the perimeter of a polygon

2

: the external boundary or surface of a body

3

a

: the outward bounds of something as distinguished from its internal regions or center : confines

b

: an area lying beyond the strict limits of a thing

Synonyms

• perimeter
• edge
• confines
• circumference
• boundary
• border
• edging

Examples of periphery in a Sentence

the dogs are confined by an invisible electronic fence that runs along the periphery of the yard

Recent Examples on the Web

Glaciers flowing toward the sea at the periphery of the 2-kilometer-thick sheet of ice were losing ice faster than snowfall could replenish them, causing their edges to recede inland. —Evan Howell, Quanta Magazine, 20 Oct. 2025

Dibling and Barry spent the half on the periphery. —Patrick Boyland, New York Times, 6 Oct. 2025

As the New York Knicks gear up for a potential NBA Finals bid in 2025-26, team president Leon Rose is tinkering around the periphery of his roster. —Alex Kirschenbaum, MSNBC Newsweek, 6 Oct. 2025

When the photographer Mary Ellen Mark arrived in New York City, in 1966, one of her strategies for finding arresting images was to attend parades and other large gatherings, seeking out subjects not in the main flow of the action but on the periphery. —Rebecca Mead, New Yorker, 5 Oct. 2025

Word History

Etymology

Middle French peripherie, from Late Latin peripheria, from Greek periphereia, from peripherein to carry around, from peri- + pherein to carry — more at bear

First Known Use

circa 1568, in the meaning defined at sense 1

Kids Definition

periphery

noun

pe·​riph·​ery pə-ˈrif-(ə-)rē 

plural peripheries

1

: the boundary or surface of a body or figure

2

: the outer or outermost part

Medical Definition

periphery

noun

pe·​riph·​ery pə-ˈrif-(ə-)rē 

plural peripheries

1

: the outward bounds of something as distinguished from its internal regions or center

2

: the regions (as the sense organs, the muscles, or the viscera) in which nerves terminate