triangle

noun
tri·​an·​gle | \ ˈtrī-ˌaŋ-gəl \

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 the way of most such triangles, unpleasantness quickly ensues. Moira Macdonald, The Seattle Times, "‘The Favourite’ review: an irresistibly nasty tale of lust, power and pet bunnies," 4 Dec. 2018 Pistachio triangles had the perfect rich flaky, honeyed (but not overwhelmingly saccharine) balance; bird’s nests, made with crunchy-crisp shredded filo, were even better. Kate Washington, sacbee, "Halal cuisine has blossomed around Sacramento. Here's a rundown of places to check out," 29 June 2018 Work triangles Cut these out of scrap ¾-inch birch or AC plywood, using the factory 90-degree corner. Roy Berendson, Popular Mechanics, "6 Simple Projects You Can Make From Scrap Wood," 21 Mar. 2018 There's also Nancy's love triangle with Jonathan and Steve to think about, not to mention the adorable, and unexpected, friendship between Dustin and Steve. Christopher Rosa, Glamour, "'Stranger Things' Season 3: Everything We Know So Far," 10 Dec. 2018 My go-to method is lifting my butt in the air and having my head down, like a triangle. Iman Hariri-kia, Teen Vogue, "Teens' Biggest Sex Questions Answered By Their Peers," 13 Nov. 2018 Vector lines intersect with ovals and triangles; glinting 1950s nostalgia starbursts are everywhere. Liz Stinson, Curbed, "Midcentury modern wallpaper lets you live out your 1950s dreams," 5 Oct. 2018 The red lane provides buses an easy path to pick up passengers at a curb triangle facing Stewart, whose lone palm tree and plastic pyramids greet travelers entering the central city. Mike Lindblom, The Seattle Times, "Bus lane carved out of busy Denny Way eastbound in South Lake Union," 28 Aug. 2018 When a downward-facing triangle appears, click on it. Kim Komando, Fox News, "10 useful Gmail settings you'll wish you knew sooner," 4 Aug. 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

16 Jan 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 \

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 \

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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