Wild chaos and noise where everyone seems to be shouting and acting crazy at once.
Created by John Milton in 'Paradise Lost' (1667) from Greek pan- (all) + daemon (demons/evil spirits). Originally the capital of Hell in his poem, it became a word for any chaotic place.
Milton literally invented this word for his epic poem—it's the name of Satan's palace. The fact that it worked so well for 'total chaos' shows how literature can create permanent additions to English.
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