/dɪˈzɑːstə(r)/ /dɪˈzæstər/

an unexpected event, such as a very bad accident, a flood or a fire, that kills a lot of people or causes a lot of damage

159 people died in the disaster

the world's worst humanitarian disaster

a very bad situation that causes problems

Losing your job doesn't have to be such a disaster.

Many business partnerships end in disaster.

a complete failure

As a teacher, he's a disaster.