Few authors get to coin a word that survives. John Milton, in his 1667 epic Paradise Lost, coined "Pandemonium" as the name of the capital city of Hell — the place where Satan and his fallen angels assemble after their defeat in heaven. Milton built the word from Greek roots: pan- ("all") plus daimonion ("demon, spirit"). Pandemonium is, literally, "the place of all the demons."
Milton's Architecture
In Book I of Paradise Lost, the fallen angels build Pandemonium as a vast hall — modelled, scholars have long noted, on the Roman Pantheon. The architectural ambition is part of Milton's argument: the demons are organised, hierarchical, and disturbingly capable. Pandemonium is grand, not chaotic. The modern meaning of "pandemonium" — uproar, confusion, complete disorder — is the opposite of what Milton was describing.
Also Read:
From Place to Adjective
For more than a century after Paradise Lost, "Pandemonium" was a proper noun — the name of Milton's fictional city, used by writers and preachers in moral discussions. By the late 18th century, the name was being used metaphorically: a riot or uproar was "a perfect pandemonium." The lower-case noun was settled by the early 19th century. The associated adjective pandemonic followed a few decades later, though it never became as common as the noun.
Coined Words That Stuck
Milton was unusual but not unique. Several other modern English words were coined by individual authors and survived because the work that contained them survived: chortle (Lewis Carroll, in Through the Looking-Glass), nerd (Dr. Seuss, in If I Ran the Zoo), quark (James Joyce's playful nonsense word, later adopted by physicist Murray Gell-Mann). Milton's contribution to English vocabulary is large — and "pandemonium" is one of his more enduring inventions.