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Synonyms

triangular

American  
[trahy-ang-gyuh-ler] / traɪˈæŋ gjə lər /

adjective

  1. pertaining to or having the form of a triangle; three-cornered.

  2. having a triangle as base or cross section.

    a triangular prism.

  3. comprising three parts or elements; triple.

  4. pertaining to or involving a group of three, as three persons, parties, or things.


triangular British  
/ traɪˈæŋɡjʊlə /

adjective

  1. Also: trigonal.  of, shaped like, or relating to a triangle; having three corners or sides

  2. of or involving three participants, pieces, or units

  3. maths having a base shaped like a triangle

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Etymology

Origin of triangular

1535–45; < Latin triangulāris, equivalent to triangul ( um ) triangle + -āris -ar 1

Explanation

Anything that looks like a a shape with three sides and three angles is triangular. If you see a triangular fin in the ocean while you’re swimming, watch out! Shark! Start looking for triangular shapes and you'll begin to see them everywhere, from a triangular slice of pizza to a tortilla chip. Like triangle, triangular is rooted in the Latin tri-, "three," and angulus, "angle or corner." You'll also occasionally find this adjective describing things that involve three people, like a triangular relationship between three best friends.

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

In August 2023, according to the release, Normandin-Parker’s friend, Luna Moore, got sick in the Uber and the driver, Vu Tran, stopped at a freeway gore point, the triangular area by the freeway’s off-ramp.

From Los Angeles Times Sep. 17, 2026

Unretouched triangular microlithic projectile points have been identified from their impact traces in the oldest occupation layers of the Obi-Rakhmat site in Uzbekistan, dating to 80,000 years ago.

From Science Daily Sep. 6, 2026

The Flatiron Building - with its unique triangular shape, narrow prow, ornamental columns and intricate decorative details - has been one of the most recognisable structures in New York City for more than a century.

From BBC Jul. 26, 2026

The triangular relationship that forms is heartbreakingly brutal yet beautiful, touching something deeper than blood.

From The Wall Street Journal Jul. 6, 2026

Her green rhinestone-studded glasses slipped down her fleshy nose as she grappled with a tall triangular package and a stuffed shopping bag.

From "The Westing Game" by Ellen Raskin

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