Bedlam is a scene of madness, chaos or great confusion. If you allow football fans onto the field after the big game, it will be pure bedlam.
The term bedlam comes from the name of a hospital in London, “Saint Mary of Bethlehem,” which was devoted to treating the mentally ill in the 1400's. Over time, the pronunciation of “Bethlehem” morphed into bedlam and the term came to be applied to any situation where pandemonium prevails. The trading floor at the New York Stock Exchange appears to be bedlam, but the traders insist it’s organized chaos.