insanity
Definitions
The state of being seriously mentally ill; madness.
Extreme foolishness or irrationality.
Examples
It is pure insanity to drive through such a dangerous storm.
The sheer insanity of the plan left everyone in the room speechless.
He claimed that the repetitive nature of his job was driving him to the brink of insanity.
Synonyms
madness lunacy dementia derangement psychosis mania craziness