exterior angle

Save This Word!

noun Geometry.

an angle formed outside parallel lines by a third line that intersects them.

an angle formed outside a polygon by one side and an extension of an adjacent side; the supplement of an interior angle of the polygon.

QUIZ

THINGAMABOB OR THINGUMMY: CAN YOU DISTINGUISH BETWEEN THE US AND UK TERMS IN THIS QUIZ?

Do you know the difference between everyday US and UK terminology? Test yourself with this quiz on words that differ across the Atlantic.

Question 1 of 7

In the UK, COTTON CANDY is more commonly known as…

candystring

candyfloss

candypuff

TAKE THE QUIZ TO FIND OUT

Origin of exterior angle

First recorded in 1885–90

Words nearby exterior angle

extenuating circumstance, extenuating circumstances, extenuation, extenuatory, exterior, exterior angle, exteriority, exteriorize, exterminate, exterminator, exterminatory

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use exterior angle in a sentence

It is in the form of a square, built round an inner courtyard, and has an immense bastion at each exterior angle.
Westminster|Sir Walter Besant
If one side of a triangle be produced, the exterior angle shall be greater than either of the interior opposite angles.
Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6|Various
The sharp edge formed by two surfaces meeting at an exterior angle.
History of Ancient Art|Franz von Reber
Posterior wings white, with a sooty spot on each near the external edge, and a very faint small mark near the exterior angle.
Illustrations of Exotic Entomology, Volume 1|Dru Drury

The proposition relating to the exterior angle was recognized by Pappus of Alexandria.
The Teaching of Geometry|David Eugene Smith

British Dictionary definitions for exterior angle

exterior angle

noun

an angle of a polygon contained between one side extended and the adjacent side

any of the four angles made by a transversal that are outside the region between the two intersected lines

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

Scientific definitions for exterior angle

exterior angle

[ ĭk-stîr′ē-ər ]

The angle formed between a side of a polygon and an extended adjacent side. Compare interior angle.