death spiral

Short definition from Wiktionary

Noun

1. 1
   The downward, corkscrew-motion of a disabled aircraft which is unrecoverably headed for a crash.
2. 2
   A manoeuvre in which a male skater spins in place while holding one hand of his female skating partner as she circles around him with one skate on the ice and one leg extended outward parallel to the ice surface, all the while slowly lowering herself until her back almost touches the ice surface.
3. 3
   The situation or course of action of one who is on a path toward some sort of inevitable catastrophic failure.
4. 4
   Synonym of ant mill (“A phenomenon where a group of army ants, separated from the main foraging party, lose the pheromone track and begin to follow one another, forming a continuously rotating circle and eventually dying of exhaustion.”).