Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “triangle”

See all translations

triangle

noun [C] uk   /ˈtraɪ.æŋ.ɡl̩/ us  
B2 a flat shape with three straight sides: an equilateral/isosceles triangle anything that has three straight sides: Which earrings did you buy in the end - the triangles or the circles? a musical instrument consisting of a thin metal bar bent into a triangle shape that is hit with a metal bar to make a sound US ( UK set square) a flat piece of metal or plastic in the shape of a triangle with one angle of 90°, used for drawing angles ( also frame) a three-sided frame for arranging the balls at the start of a game of billiards , pool, etc.
More examples
(Definition of triangle from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of triangle?
Add Cambridge dictionaries to your browser to your website

Definitions of “triangle” in other dictionaries

Word of the Day

make believe

believing or imagining things that appear to be attractive or exciting, but are not real

Word of the Day

Lies, lies, lies!

by Kate Woodford,
February 25, 2015
​​​ According to sociologists (=people who study the relationships between people living in groups), we are good at lying. As a species, we have developed a remarkable ability to deceive each other (= persuade each other that something false is true). Being able to say things that are not true can help with

Read More 

showrooming noun

February 23, 2015
the activity of examining a product in a physical store and then making the purchase with an online retailer Amazon’s new smartphone is specifically designed to make showrooming fast and easy.

Read More