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1. An event resulting in great loss and misfortune
   "the whole city was affected by the irremediable catastrophe";
   - calamity, disaster, tragedy, cataclysm
    
2. A state of extreme (usually irremediable) ruin and misfortune
   "lack of funds has resulted in a catastrophe for our school system";
   - disaster
    
3. A sudden violent change in the earth's surface
   - cataclysm
    
4. (mathematics) a type of bifurcation, where a system shifts suddenly to a different state or behaviour

Derived forms: catastrophes

Type of: adversity, bad luck, geological phenomenon, hard knocks, hardship, misfortune

Encyclopedia: Catastrophe