exterior angle

noun

1

: the angle between a side of a polygon and an extended adjacent side

2

: an angle formed by a transversal as it cuts one of two lines and situated on the outside of the line

Illustration of exterior angle

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Examples of exterior angle in a Sentence

Recent Examples on the Web

It is known that the sum of the exterior angles of a convex polygon is always 360º. Since an exterior angle of a right angle is also a right angle, our four right angles would take up the entire 360º of the octagon’s exterior-angle measure. —Quanta Magazine, 18 Nov. 2020

It is known that the sum of the exterior angles of a convex polygon is always 360º. Since an exterior angle of a right angle is also a right angle, our four right angles would take up the entire 360º of the octagon’s exterior-angle measure. —Quanta Magazine, 18 Nov. 2020

Word History

First Known Use

1756, in the meaning defined at sense 1

Kids Definition

exterior angle

noun

: any of the four angles formed by a line cutting across two other lines and located on the outside of those lines