In the poem, Milton describes "Pandemonium" as the capital city of Hell and the place where the fallen angels gather after their rebellion against God.
Milton created the word by combining the Greek words:
* pan- (all, every)
* daimon (demon)
Thus, pandemonium literally means "all demons" and refers to a place of great noise, confusion, and chaos, reflecting the unruly nature of the fallen angels.
The word quickly entered the English language to describe situations of wild uproar and disorder.