Definition of "muckraker" [muck•rak•er]

• One who investigates and exposes issues of corruption that often violate widely held values; e.g. one who exposes political corruption or the poor conditions in prisons. (noun)
• A sensationalist, scandal-mongering journalist, one who is not driven by any social principles. (noun)
• One of a group of American investigative reporters, novelists and critics of the Progressive Era (the 1890s to the 1920s) (noun)

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• "He was what they described as a muckraker earlier."
• "Sort of like what the TPM muckraker is to Talking Points Memo."
• "Of the school of earnest young writers at whom the word muckraker had been thrown in opprobrium, and by whom it had been caught up as a title of honor, Everett was among the younger and less conspicuous."