debacle

An event or enterprise that ends suddenly and disastrously, often with humiliating consequences.

The event proved to be a great debacle for the partisans of this prognosticator.

The result is a military approach which maximizes political tensions with Russia […] and lays the ground for a military debacle.

A breaking up of a natural dam, usually made of ice, by a river and the ensuing rush of water.

[…] so that in extreme cases the latter may even be dammed up for a time, and a debacle be the consequence, when the main river overcomes the resistance opposed to it, […]

For several months after the debacle just described, the river Dranse, having no settled channel, shifted its position continually […]