The most contemptible and dishonorable person; a supreme villain or utterly unprincipled individual.
From 'arch-' (chief, supreme) + 'scoundrel' (possibly from Italian 'ascondere,' to hide, or from romance languages meaning dishonest person). Peak form of moral condemnation in older literature.
Shakespeare's villains—Iago, Macbeth's evil counselors—are archscoundrels. The word carried real venom in societies that relied on honor; calling someone an archscoundrel was one of the worst possible insults, suggesting they threatened social order itself.
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