a word that is opposite in meaning to another word
⇒ “sad” is an antonym of “happy”
Webster’s New World College Dictionary, Fourth Edition, compiled by the
editors of Webster’s New World Dictionaries. Copyright © 2010 by Houghton
Mifflin Harcourt. Published by Houghton Mifflin Harcourt. All rights reserved.
Word origin of 'antonym'
with altered sense (as if < anti-
) < Gr antōnymia
, a pronoun < anti-
, equal to, instead of, opposite (see anti-
) + onyma