The definition of antonyms are words that have contrasting meanings.(noun)
An example of antonyms are light and dark.
See antonym in Webster's New World College Dictionary
Origin: with altered sense (as if < anti-) < Gr antōnymia, a pronoun < anti-, equal to, instead of, opposite (see anti-) + onyma, name
See antonym in American Heritage Dictionary 4
Origin: + -onym.
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