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

Illustration of interior angle
  • agh bgh ghd ghc interior angle sense 2

Examples of interior angle in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
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 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

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

Rhymes for interior angle

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Browse Nearby Words

interior
interior angle
interior ballistics
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Cite this Entry

“Interior angle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/interior%20angle. Accessed 5 Aug. 2026.

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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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