adjective
insane
in-SAYN/ɪnˈseɪn/
Severely disconnected from sound judgment or reality.
Launching a bicycle off the roof without a landing place is an insane idea.
Etymology
The literal image is ‘not healthy,’ specifically applied to the mind. From describing mental unsoundness, English extended insane to actions judged irrational or extremely foolish.
In context
It's an insane idea to go into battle, just the two of them,
This was an insane idea, because if lightning did strike this rod,
More examples
- It seems insane to spend our entire savings on one bet.
- The jury finds him legally insane at the time of the crime.
- In the novel, the prisoner fears he is going insane.
Forms
insane
insanity noun — Severe mental disturbance or wildly unreasonable behavior.
insanely adverb — In a wildly unreasonable or irrational manner.
Similar words
- irrational
- Lacking logical judgment without necessarily losing contact with reality.
- delusional
- Holding firmly to false beliefs despite clear contrary evidence.