disaster as in a state of extreme (usually irremediable) ruin and misfortune

• "lack of funds has resulted in a catastrophe for our school system"
• "his policies were a disaster"

Synonyms

• catastrophean event resulting in great loss and misfortune; a state of extreme (usually irremediable) ruin and misfortune; a sudden violent change in the earth's surface

disaster as in an event resulting in great loss and misfortune

• "the whole city was affected by the irremediable calamity"
• "the earthquake was a disaster"

Synonyms

• calamityan event resulting in great loss and misfortune
• catastrophean event resulting in great loss and misfortune; a state of extreme (usually irremediable) ruin and misfortune; a sudden violent change in the earth's surface
• tragedyan event resulting in great loss and misfortune; drama in which the protagonist is overcome by some superior force or circumstance
• cataclysma sudden violent change in the earth's surface ; an event resulting in great loss and misfortune

disaster as in an act that has disastrous consequences