# interior angle

## noun

1
: the inner of the two angles formed where two sides of a polygon come together
2
: any of the four angles formed in the area between a pair of parallel lines when a third line cuts them

## Illustration of interior angle

• agh bgh ghd ghc interior angle sense 2

## Examples of interior angle in a Sentence

Recent Examples on the Web At this point the initial polygon has been reduced to a triangle, whose interior angle sum is known to be 180 degrees. Patrick Honner, Quanta Magazine, 22 Mar. 2024 This is a recursive relationship: The interior angle sum for an n-gon is 180 degrees more than the interior angle sum for an (n − 1)-gon. Patrick Honner, Quanta Magazine, 22 Mar. 2024 The result: a round-rimmed pint with an interior angle designed to give your pour the perfect head and aroma every time. Joe Jackson, Outside Online, 28 Jan. 2015 With each interior angle measuring 108 degrees, three pentagons leave a gap and four begin to overlap. Marisa Sloan, Discover Magazine, 21 July 2021 Dehn focused on the interior angles formed where two faces of a three-dimensional shape meet. Quanta Magazine, 31 Oct. 2019 Both are three-dimensional structures, but each has a very different geometry: Their layouts are different, the curvature of their exteriors is different, their interior angles are different. Quanta Magazine, 9 Apr. 2018

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'interior angle.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

## Word History

First Known Use

1756, in the meaning defined at sense 1

Time Traveler
The first known use of interior angle was in 1756

interior angle

## Cite this Entry

“Interior angle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/interior%20angle. Accessed 28 May. 2024.

## Kids Definition

interior angle

noun
: any of the four angles formed in the area between a pair of lines when a third line cuts them
Last Updated: - Updated example sentences
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