From The Collaborative International Dictionary of English v.0.48:
Insane \In*sane"\, a. [L. insanus. See In- not, and Sane.]
1. Exhibiting unsoundness or disorder of mind; not sane; mad;
deranged in mind; delirious; distracted. See Insanity,
2.
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2. Used by, or appropriated to, insane persons; as, an insane
hospital.
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3. Causing insanity or madness. [R.]
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Or have we eaten on the insaneroot
That takes the reason prisoner ? --Shak.
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4. Characterized by insanity or the utmost folly; chimerical;
unpractical; as, an insane plan, attempt, etc.
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I know not which was the insane measure. --Southey.
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