The condition in which a large number of people with no real direction or purpose suddenly find themselves in conflict with each other, and simultaneously decide - subconsciously - to meet in the middle, which somehow manages to only make things exponentially worse.
Easily prevented by situational awareness, which is generally checked at the door when entering consumer supercenters, convention halls, and other buildings/spaces which see generous amounts of human traffic.
The sort of thing that might happen at a 6-way intersection if the traffic light were broken.
"Everything was cool, until someone started running. Then other people started to panic and they started running, and no one really knew which way they were even supposed to be running; eventually it just turned into one big Wal-Mart Clusterfuck.
I don't think anyone even knows what that first guy was running from."
Based on the theory proposed by R. M. Nixon, a self-perpetuating comedy of errors; not to be confused with a regular clusterfuck, which ends quietly when the last error can't spawn a chain reaction of new ones.
So after Ed has to change his shirt because his wife spilled coffee on him, he misses his bus, calls a taxi... the driver jumps a curb, blows out a rear tire, doesn't have a spare, and when the police come he fails the balloon test and Ed has to go in with the police and fill out a report? That, my friend, is a Domino Clusterfuck!
When the shoppers of costco all jam up the walking area wating for a popular sample. Impossible to get through, and usually ends up with the sample running out, causing rage.
I was trying to get myself some bread, but that monthly smoothie sample stand was causing a Costco Clusterfuck, and getting through it was impossible.