triangle

American  

[trahy-ang-guhl] / ˈtraɪˌæŋ gəl /

noun

1. a closed plane figure having three sides and three angles.

2. a flat triangular piece, usually of plastic, with straight edges, used in connection with a T square for drawing perpendicular lines, geometric figures, etc.

3. any three-cornered or three-sided figure, object, or piece.

   a triangle of land.

4. a musical percussion instrument that consists of a steel triangle, open at one corner, that is struck with a steel rod.

5. a group of three; triad.

6. a situation involving three persons, especially one in which two of them are in love with the third.

7. Astronomy. Triangle, the constellation Triangulum.

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triangle British  

/ ˈtraɪˌæŋɡəl /

noun

1. geometry a three-sided polygon that can be classified by angle, as in an acute triangle, or by side, as in an equilateral triangle. Sum of interior angles: 180°; area: 1/ 2 base × height

2. any object shaped like a triangle

3. any situation involving three parties or points of view See also eternal triangle

4. music a percussion instrument consisting of a sonorous metal bar bent into a triangular shape, beaten with a metal stick

5. a group of three

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triangle Scientific  

/ trī′ăng′gəl /

1. A closed geometric figure consisting of three sides.

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triangle Idioms  

1. see eternal triangle.

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Other Word Forms

• triangled adjective

Etymology

Origin of triangle

First recorded in 1350–1400; Middle English, from Latin triangulum, noun use of neuter of triangulus “three-cornered”, tri-, angle ¹

Example Sentences

Air New Zealand AIR 3.19%increase; green up pointing triangle suspended its guidance for the second half of 2026, citing volatility in jet fuel markets stemming from the war in Iran.

From The Wall Street Journal

Beijing is channeling substantial investment into the so-called "lithium triangle" — the mineral-rich belt across Argentina, Bolivia, and Chile that holds 56% of the world's lithium reserves.

From BBC

BP BP 1.33%increase; green up pointing triangle has called on shareholders to vote against a resolution that would require it to publish more detailed disclosures on how it takes investment decisions.

From The Wall Street Journal

Gap GAP -1.95%decrease; red down pointing triangle logged lower profit in its latest quarter as declining sales at its Athleta brand continue to dent results.

From The Wall Street Journal

Target TGT 0.23%increase; green up pointing triangle said it plans to open more than 30 locations this year, part of the retailer’s strategy to drive long-term, sustainable growth by investing in its stores.

From The Wall Street Journal

Related Words

• adultery
• affair
• courtship
• dalliance
• devotion
• fling
• flirtation
• infidelity
• involvement
• liaison
• love
• passion
• relationship
• tryst