pan ‧ de ‧ mo ‧ ni ‧ um /ˌpændəˈməʊniəm, ˌpændɪˈməʊniəm $ -ˈmoʊ-/ BrE AmE noun [uncountable]
[ Date: 1600-1700 ; Origin: Pandaemonium city of evil spirits in the poem Paradise Lost (1667) by John Milton, from Greek pan- ( ⇨ ↑ pan- ) + daimon 'evil spirit' ]
a situation in which there is a lot of noise because people are angry, confused or frightened SYN chaos :
There was complete pandemonium in the kitchen.
When the verdict was read pandemonium broke out in the courtroom.