right triangle

American  

noun

1. a triangle having a right angle (contrasted with oblique triangle).

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right triangle British  

noun

1. Also called (in Britain and certain other countries): right-angled triangle.  a triangle one angle of which is a right angle

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right triangle Scientific  

1. A triangle having a right angle.

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right triangle Cultural  

1. A triangle that contains a right angle.

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Etymology

Origin of right triangle

First recorded in 1920–25

Example Sentences

In this equation, a, b and c represent the lengths of the three sides of a right triangle, a triangle with a 90-degree angle between two of its sides.

From Scientific American • Apr. 10, 2023

Imagine a right triangle with one side that lies flat against a table and another that shoots straight up from where it meets the first side at a right angle.

From Scientific American • Apr. 10, 2023

The numbers 3 and 4 represent the measurements of each leg of a right triangle in which 5 is the length of the hypotenuse.

From Seattle Times • Dec. 12, 2022

You may also remember the simple equation, discovered by Pythagoras thousands of years ago, that describes a right triangle: A squared + B squared = C squared.

From Seattle Times • Dec. 12, 2022

In modern schools, children learn of Pythagoras for his famed theorem: the square of the hypotenuse of a right triangle is equal to the sum of the squares of the other two sides.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife