catastrophe

noun

1. (countable, uncountable)Any large and disastrous event of great significance.

   “The Chernobyl disaster was a catastrophe.”

   “Last night, after the brief sitting of the House of Lords, and before catastrophe befell the Government in the Commons, I had a long chat with the Premier, in which he discussed the Home Rule question and his relations with it in perfectly frank manner.”

   “Between these high lights accumulated disaster, social catastrophe.”

   “Am I not a man? And is a man not stupid? I'm a man, so I married. Wife, children, house, everything. The full catastrophe.”

   “For years, Mao Da, an environmental researcher, has studied the plastic industry in Wen’an County, near Beijing. Workers there used to sort through food and medical waste by hand, he said. Nonrecyclable material was buried in pits near farmland. “It was an environmental and public health catastrophe,” Mr. Mao said.”

2. (countable, uncountable)A disaster beyond expectations.
3. (countable, uncountable)The dramatic event that initiates the resolution of the plot; the dénouement.

   “Pat : he comes like the Cataſtrophe of the old Comedie : my Cue is villanous Melancholly, with a ſighe like Tom o’ Bedlam.”

4. (countable, uncountable)A type of bifurcation, where a system shifts between two stable states.