from The American Heritage® Dictionary of the English Language, 4th Edition
- n.pl. Two angles whose sum is 90°.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A pair of angles that sum to a right angle.
from the GNU version of the Collaborative International Dictionary of English
- adj. two angles whose sum is 90°.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. two angles whose sum is a right angle
Complementary in the sense of completing, i.e. they form a complete right angle. (Wiktionary)