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Synonyms

triangular

American  
[trahy-ang-gyuh-ler] / traɪˈæŋ gyə 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  
/ traɪˌæŋɡjʊˈlærɪtɪ, 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

  • subtriangular adjective
  • subtriangularity noun
  • triangularity noun
  • triangularly adverb

Etymology

Origin of triangular

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

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.

Their study, titled "Interleaved bond frustration in a triangular lattice antiferromagnet," examines how multiple forms of frustration can arise in these systems.

From Science Daily • Mar. 16, 2026

The FAA also cordoned off a triangular zone south of Key West.

From Salon • Jan. 12, 2026

The FLM 136 drone closely resembles the Shahed-136, with a triangular wingspan measuring just over 8 feet, according to the company’s website.

From The Wall Street Journal • Dec. 3, 2025

The course began and ended at Palisades Village Green, a small triangular park in the middle of the downtown area.

From Los Angeles Times • Nov. 27, 2025

He showed Chamberlain the new brigade flag: triangular, white, with a blue border, a red Maltese Cross in the center.

From "The Killer Angels: The Classic Novel of the Civil War" by Michael Shaara

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.