quad·​ri·​lat·​er·​al | \ ˌkwä-drə-ˈla-t(ə-)rəl How to pronounce quadrilateral (audio) \

Definition of quadrilateral

 (Entry 1 of 2)

: a polygon of four sides



Definition of quadrilateral (Entry 2 of 2)

: having four sides

Examples of quadrilateral in a Sentence

Recent Examples on the Web: Noun

In the course of trying to prove that certain other kinds of orbit closures don’t exist, the mathematician Alex Wright (who was collaborating with Mirzakhani) stumbled across the first hints of the new quadrilaterals with optimal dynamics. Quanta Magazine, "Why Mathematicians Like to Classify Things," 15 Aug. 2017 The two were, in a sense, trying to prove that shapes like these quadrilaterals don’t exist. Quanta Magazine, "New Shapes Solve Infinite Pool-Table Problem," 8 Aug. 2017 The new 2,700-square-foot space feels like a geometric funhouse — quadrilaterals of wood overhead, an enveloping half-circle over the open kitchen, and the hypotenuse of the bar slanting through the lounge. Tan Vinh, The Seattle Times, "Art of the Table lounge aims high — too high?," 27 Apr. 2017

Recent Examples on the Web: Adjective

The Trump administration should help further incorporate India into this emerging quadrilateral relationship between themselves, Japan, and Australia. Evan Moore, National Review, "Strengthen the U.S.–India Relationship," 1 Feb. 2018 Admiral Harris’s proposal of a quadrilateral security grouping, given at a forum hosted by the Observer Research Foundation, is certain to capture Beijing’s attention. Ellen Barry, New York Times, "What China Has Been Building in the South China Sea," 2 Mar. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'quadrilateral.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of quadrilateral


1650, in the meaning defined above


1656, in the meaning defined above

History and Etymology for quadrilateral


Latin quadrilaterus four-sided, from quadri- + later-, latus side

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Statistics for quadrilateral

Last Updated

6 Jul 2019

Look-up Popularity

Time Traveler for quadrilateral

The first known use of quadrilateral was in 1650

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English Language Learners Definition of quadrilateral

geometry : a flat shape that has four sides and four angles


quad·​ri·​lat·​er·​al | \ ˌkwä-drə-ˈla-tə-rəl How to pronounce quadrilateral (audio) \

Kids Definition of quadrilateral

: a flat geometric figure of four sides and four angles


quad·​ri·​lat·​er·​al | \ ˌkwäd-rə-ˈlat-ə-rəl, -ˈla-trəl How to pronounce quadrilateral (audio) \

Medical Definition of quadrilateral

: having four sides a quadrilateral muscle

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Comments on quadrilateral

What made you want to look up quadrilateral? Please tell us where you read or heard it (including the quote, if possible).


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