a sudden accident or a natural catastrophe that causes great damage or loss of life:159 people died in the disaster [mass noun]:disaster struck within minutes of take-off
[as modifier] denoting a genre of films that use natural or accidental catastrophe as the mainspring of plot and setting:a disaster movie
an event or fact that has unfortunate consequences:a string of personal disasters [mass noun]:reduced legal aid could spell financial disaster
informal a person or thing that is a complete failure:lunch had turned out to be a total disaster
