right triangle

noun

variants or British right-angled triangle

plural right triangles

: a triangle having a right angle see triangle illustration compare acute triangle, obtuse triangle

Examples of right triangle in a Sentence

Recent Examples on the Web

In a geometry example, Bansal drew a right triangle with legs of length 3 and 4 and asked for the sine of an angle. — Ray Ravaglia, Forbes.com, 21 July 2026

By way of analogy, in flat space, the hypotenuse of a right triangle is always a2 + b2 = c2. — Daniel Garisto, Quanta Magazine, 7 Nov. 2025

Any Pythagorean triple — including 3, 4, and 5 — also gives the lengths of the three sides of a right triangle. — Ari Daniel, NPR, 16 Sep. 2025

Vega, Deneb and Altair make a right triangle with the right angle at Deneb, this is called the Summer Triangle. — Jesse Emspak, Space.com, 22 Aug. 2025

Word History

First Known Use

1583, in the meaning defined above

Rhymes for right triangle

• angle
• bangle
• dangle
• jangle
• mangle
• strangle
• tangle
• wrangle
• disentangle
• entangle
• quadrangle
• untangle

Kids Definition

right triangle

noun

: a triangle having a right angle