tri·​an·​gle | \ ˈtrī-ˌaŋ-gəl How to pronounce triangle (audio) \

Definition of triangle

1 : a polygon having three sides — compare spherical triangle
2a : a percussion instrument consisting of a rod of steel bent into the form of a triangle open at one angle and sounded by striking with a small metal rod
b : a drafting instrument consisting of a thin flat right-angled triangle of wood or plastic with acute angles of 45 degrees or of 30 degrees and 60 degrees
3 : a situation in which one member of a couple is involved in a love affair with a third person

Illustration of triangle

Illustration of triangle

triangle 1: 1 equilateral, 2 acute, 3 obtuse, 4 scalene, 5 isosceles, 6 right triangle

Examples of triangle in a Sentence

She cut the sandwiches into triangles.
Recent Examples on the Web Also, a beautiful silk scarf (worn folded into a triangle and draped over your shoulders), a watch or -- my personal favorite -- big earrings can be quite impactful. CNN, 6 May 2022 The eight-episode series starring Gavin Casalegno, Lola Tung, Jackie Chung, Rachel Blanchard, Christopher Briney and Tom Everett Scott centers on a love triangle between a girl and two brothers is slated to debut on June 17. Gil Kaufman, Billboard, 5 May 2022 However, in this version, a group of three people — representing the Father, Son, and Holy Ghost – can hold hands and form a triangle in order to remain safe. Corinne Sullivan, Woman's Day, 5 May 2022 The film follows a love triangle between three tennis players on and off the court; Zendaya stars as Tashi, a tennis coach who trains her husband, Art (Mike Faist), who's competing to become Grand Slam champion. Sabrina Park, Harper's BAZAAR, 21 Apr. 2022 An image of two robot hands forming a triangle then flashes on-screen with the time-stamp: 1993-2021. Emily Zemler, Rolling Stone, 14 Apr. 2022 Coloring any of them either red or blue forces a triangle to have all edges of the same color, as shown in the following table. Quanta Magazine, 8 Apr. 2022 While the first movie followed Laura falling in love with Massimo after his kidnapping of her, the sequel promises jealousy, betrayal and a possible love triangle. Julia Moore,, 7 Apr. 2022 But during her first breeding season as queen, which began in November 2021 and concluded in March 2022, a messy love triangle threatened to weaken her grip on power. New York Times, 6 Apr. 2022 See More

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

First Known Use of triangle

14th century, in the meaning defined at sense 1

History and Etymology for triangle

Middle English, from Anglo-French, from Latin triangulum, from neuter of triangulus triangular, from tri- + angulus angle

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Time Traveler for triangle

Time Traveler

The first known use of triangle was in the 14th century

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Dictionary Entries Near triangle



triangle crab

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Statistics for triangle

Last Updated

10 May 2022

Cite this Entry

“Triangle.” Dictionary, Merriam-Webster, Accessed 22 May. 2022.

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More Definitions for triangle


tri·​an·​gle | \ ˈtrī-ˌaŋ-gəl How to pronounce triangle (audio) \

Kids Definition of triangle

1 : a flat geometric figure that has three sides and three angles
2 : something that has three sides and three angles a triangle of land
3 : a musical instrument made of a steel rod bent in the shape of a triangle with one open angle


tri·​an·​gle | \ ˈtrī-ˌaŋ-gəl How to pronounce triangle (audio) \

Medical Definition of triangle

: a three-sided region or space and especially an anatomical one — see anterior triangle, carotid triangle, femoral triangle, posterior triangle, suboccipital triangle

More from Merriam-Webster on triangle

Nglish: Translation of triangle for Spanish Speakers

Britannica English: Translation of triangle for Arabic Speakers Encyclopedia article about triangle


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