antonymic

/ˌæntəˈnɪmɪk/
adjective
  1. Relating to or having the nature of an antonym; expressing opposition in meaning.
    • The words "begin" and "end" have an antonymic relationship.
    • In the antonymic pair "light" and "dark," each word defines the other.
    • The antonymic structure of the poem highlights the contrast between joy and sorrow.
Antonyms
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