The verb affront means “to insult, to offend deliberately”; the noun means “insult” and takes to or, less frequently, of: I couldn’t forgive his affront to [of] his mother. Effrontery is “impudence, boldness, audacity, presumption”: She then had the effrontery to ask a favor.Note: You may download the Grammar eBook Build Your Vocabulary and get all 406 vocabulary words.
—Kenneth G. Wilson The Columbia Guide to Standard American English (1993)
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