The most accomplished deceiver or hypocrite; someone supremely skilled at hiding their true feelings or intentions.
From 'arch-' (supreme) and 'dissembler' (one who dissembles or disguises true feelings), from Middle English via Old French 'dissembler' (to hide or disguise). Popular in 17th-18th century literature as a way to describe moral corruption.
Shakespeare and his contemporaries loved this word—calling a character an 'archdissembler' was the ultimate insult in court politics, suggesting someone was so dishonest they'd transcended ordinary lying into an art form.
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