interior angle

noun Geometry.

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

an angle formed within a polygon by two adjacent sides.

Origin of interior angle

First recorded in 1750–60

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for interior angle

interior angle

noun

an angle of a polygon contained between two adjacent sides

any of the four angles made by a transversal that lie inside 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

interior angle in Science

interior angle

[ĭn-tîr′ē-ər]

Any of the four angles formed inside two straight lines when these lines are intersected by a third straight line.

An angle formed by two adjacent sides of a polygon and included within the polygon. Compare exterior angle.