What does polygon mean?
A polygon is a closed, flat figure made from straight line segments called sides, which meet at corners called vertices. The term is most familiar from geometry, where polygons are classified according to their number of sides and by properties such as regularity, convexity, and symmetry; examples include the triangle, square, pentagon, and hexagon. The word is also used more broadly for angular boundaries in maps, architecture, graphic design, and computer graphics. A polygon is specifically two-dimensional, so it differs from a polyhedron, which is a solid with multiple polygonal faces. Its name reflects its Greek origin and literally describes a figure with many angles, although the word applies even to a three-sided polygon.
nounA polygon is a closed plane figure made up of straight line segments, or sides, that meet at vertices. In geometry, the number of sides and angles determines the polygon's type, such as a triangle, quadrilateral, or pentagon.
- A closed two-dimensional plane figure bounded by straight line segments.
- A geometric figure considered as a boundary made of multiple sides, whether in pure mathematics or in design, architecture, and surveying.
"The architect designed the new library as a large polygon with glass panels along its exterior."
"The students learned how to calculate the area of a regular polygon using formulas based on its sides and apothem."
"The map marks the city boundary as an irregular polygon that follows the river and major roads."
The usual plural is “polygons.”
"The program automatically converts the shapes into polygons."
Polygon comes from Greek roots meaning “many-angled”: it is the general name for a shape with three or more straight sides.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does polygon come from?
The English word polygon comes from the Greek polygōnos, meaning “many-angled.” It is formed from polys, “many,” and gōnia, an angle or corner. The term entered English through Latin and was used in mathematical writing from the early modern period. Its Greek combining elements continue in many English words beginning with poly-, such as polygamy, polyglot, and polynomial.
Related word forms
How polygon is actually used
In general usage, polygon is most common in geometry, but it is also used for angular outlines in architecture, cartography, graphics, and surveying. A polygon normally has at least three sides; “polygon” should not be used for an open or curved boundary.
Easily confused with polygon
A polygon is a flat, two-dimensional figure, whereas a polyhedron is a three-dimensional solid with flat polygonal faces.