unmask v. + Add to list US //ənˈmæsk// UK //ʌnmˈɑːsk// un·mask Archaic SynonymsAntonymsEtymology Synonyms uncloak Antonyms maskOrigin From un- + mask. Compare typologically reveal (see more). Idioms1 entry01unmask one's batteriesTo begin a decisive action, especially one that reveals one’s true strength or character.