A person who opposes or exposes humbug, especially fraudulent or deceptive practices; someone devoted to uncovering dishonesty and pretense.
From anti- (against) + humbug (from 1750s London slang, origin unclear but possibly combining 'hum' meaning to deceive + 'bug' from bugbear, something frightening) + -ist (one who practices). The term is humorous and somewhat archaic.
Victorian-era antihumbuggists were basically the original fact-checkers and myth-busters—they loved publicly exposing fake spiritualists, medical charlatans, and con artists, which made them folk heroes in their day.
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