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.

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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

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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

At their point of contact, a large triangular slice of the addition is cut away, exposing the sides of the boxes and creating a street-level plaza.

From The Wall Street Journal • Mar. 20, 2026

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

From Salon • Jan. 12, 2026

Above S Monocerotis, a group of young stars forms a simple triangular pattern.

From Science Daily • Dec. 25, 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

The triangular shape of the boy leaning on the ledge gives stability to the painting, which helps to suspend the fleeting instant in time.

From "History of Art, Volume 1" by H.W. Janson

Related Words

• trilateral