triangle

noun
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

In John Doyle’s revival, Anika Noni Rose stars as a femme fatale with David Aron Damane and Clifton Duncan as the other points in this love triangle. Alexis Soloski, New York Times, "11 Plays and Musicals to Go to in N.Y.C. This Weekend," 21 June 2018 And Calyx, like a lot of reality TV producers, is really interested in pushing this love triangle to its breaking point. Ella Cerón, Teen Vogue, "Tyler Posey on “Blumhouse’s Truth or Dare” and Why He Loves Horror," 12 Apr. 2018 So far from being impossibly flat, this triangle would appear unmistakably triangular. Quanta Magazine, "Solution: ‘Is Infinity Real?’," 30 June 2016 Terra-cotta tones, naturally, are everywhere: splashed through the pattern of a rug, in the triangles of a mural that family friend and artist Laura Spinner hand-painted onto the walls of the dining room. Robert Ruffino, House Beautiful, "This Gorgeous House Was Inspired by a Southwestern Road Trip," 28 May 2019 In addition to the Greenway’s beautiful welds and curvaceous rear triangle, every part that goes onto it is chosen by you, Weird Science-style. Bradley Ford, Popular Mechanics, "The Best Commuter Bikes for Any Commute," 16 May 2019 From workplace shakeups to surprise pregnancies and romantic triangles, the Season 5 finale of Younger left fans with a lot of unanswered questions. Lauren Alexis Fisher, Harper's BAZAAR, "Miriam Shor On Season 6 of 'Younger' and How Diana Trout Empowered Her to Pursue Directing," 13 May 2019 Continue making triangular folds until the whole flag is folded into one triangle of blue and white stars. Rebecca Deczynski, Good Housekeeping, "The Proper Etiquette for Flying the American Flag, Including on Memorial Day," 10 May 2019 For years, the epicenter of the conflict has been in a triangle of towns and cities in the northeast corner of Sinai on the Mediterranean coast. Brian Rohan, Fox News, "Egypt arming Sinai tribesmen in fight against Islamic State," 27 Sep. 2018

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.

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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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Statistics for triangle

Last Updated

19 Jun 2019

Look-up Popularity

Time Traveler for triangle

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

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More Definitions for triangle

triangle

noun

English Language Learners Definition of triangle

: a shape that is made up of three lines and three angles
: something that is shaped like a triangle
: a musical instrument that is made of a steel rod bent into the shape of a triangle and that you play by hitting with a metal rod

triangle

noun
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

triangle

noun
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

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More from Merriam-Webster on triangle

Rhyming Dictionary: Words that rhyme with triangle

Spanish Central: Translation of triangle

Nglish: Translation of triangle for Spanish Speakers

Britannica English: Translation of triangle for Arabic Speakers

Britannica.com: Encyclopedia article about triangle

Comments on triangle

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