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complementary angle

noun Mathematics.
  1. either of two angles that added together produce an angle of 90°.
Compare supplementary angle.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for complementary angles

complementary angle

noun
  1. either of two angles whose sum is 90°Compare supplementary angle
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
complementary angles in Science

complementary angles

[kŏm′plə-mĕn′tə-rē]
  1. Two angles whose sum is 90°.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.