ETYM French débâcle, from débâcler to unbar, break loose; pref. dé- (prob. = Latin dis) + bâcler to bolt, from Latin baculum a stick.
1. A sudden and violent collapse; SYN. fiasco.
2. Flooding caused by a tumultuous breakup of ice in a river during the spring or summer.

(French) complete rout or failure; stampede; ice-break; flood.