A person who publicly says that someone or something is bad, wrong, or guilty; someone who makes accusations or condemns publicly.
From denounce + -er (suffix forming agent nouns for one who performs an action). The suffix -er is productive in English, creating nouns for people who do the root verb.
A denouncer has real power—they're not just criticizing privately, they're making a public statement that forces others to take sides, which is why throughout history, denouncers have been both celebrated as truth-tellers and feared as dangerous accusers.
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