one of two opposite and equal angles formed by the intersection of two lines.
Origin of vertical angle
First recorded in 1565–75
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
geometry the pair of equal angles between a pair of intersecting lines; opposite anglesAlso called: vertically opposite angles
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
Two angles formed by two intersecting lines and lying on opposite sides of the point of intersection.
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