polygon

American  

[pol-ee-gon] / ˈpɒl iˌgɒn /

noun

1. a figure, especially a closed plane figure, having three or more, usually straight, sides.

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polygon British  

/ pəˈlɪɡənəl, ˈpɒlɪˌɡɒn /

noun

1. a closed plane figure bounded by three or more straight sides that meet in pairs in the same number of vertices, and do not intersect other than at these vertices. The sum of the interior angles is ( n –2) × 180° for n sides; the sum of the exterior angles is 360°. A regular polygon has all its sides and angles equal. Specific polygons are named according to the number of sides, such as triangle, pentagon, etc

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polygon Scientific  

/ pŏl′ē-gŏn′ /

1. A closed plane figure having three or more sides. Triangles, rectangles, and octagons are all examples of polygons.

2. ◆ A regular polygon is a polygon all of whose sides are the same length and all of whose interior angles are the same measure.

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polygon Cultural  

1. In geometry, a closed figure having three or more sides and lying on one plane.

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Other Word Forms

• polygonal
  adjective
• polygonally
  adverb
• subpolygonal
  adjective
• subpolygonally
  adverb

Etymology

Origin of polygon

First recorded in 1560–70; from Latin polygōnum, from Greek polýgōnon, noun use of neuter of polýgōnos “many-angled”; see poly-, -gon

Explanation

A polygon is a closed shape with straight sides. Rectangles, triangles, hexagons, and octagons are all examples of polygons. The word polygon comes from the Greeks, like most terms in geometry, which they invented. It simply means many (poly) angles (gon). A polygon can’t have any curves or any gaps or openings in its shape. If you want to describe something as angular and closed, like, say, the Pentagon, or a stop sign, you could call it "polygonal."

Example Sentences

We wander back wet, down to Castillo Square, down to the ghosts of Bar Milano, a stand-in for Bar Torino, and Café Suizo, where the fiesta unravels in insults, a love polygon and fisticuffs.

From Salon • Nov. 8, 2025

A love triangle stretches to encompass more people and form a shifting polygon.

From The Wall Street Journal • Oct. 9, 2025

County officials correctly used the Genasys software to draw a polygon that would alert only residents near the fire, which sparked in West Hills.

From Los Angeles Times • Mar. 6, 2025

They whittled down the area to what they came to call the polygon, which left them with several hundred homes around First Avenue in Massapequa Park, law enforcement officials said.

From Seattle Times • Jul. 20, 2023

The huge cypress trees she and her father pass on their morning walk are shimmering kaleidoscopes, each needle a polygon of light.

From "All the Light We Cannot See" by Anthony Doerr

Related Words

• shape