the use of a word in a sense opposite to its proper meaning.
Origin of antiphrasis
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
rhetoric the use of a word in a sense opposite to its normal one, esp for ironic effect
Word Origin for antiphrasis
C16: via Late Latin from Greek, from anti- + phrasis, from phrazein to speak
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