Word forms: unmasks
verb If you unmask someone or something bad, you show or make known their true nature or character, when they had previously been thought to be good. [V n] ⇒ Elliott unmasked and confronted the master spy and traitor Kim Philby. [V n] ⇒ He managed to pass top secret documents to East Berlin for many years before he was unmasked in 1974.
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