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a. Of, exhibiting, or afflicted with mental derangement. Not used in psychiatric diagnosis.
b. Characteristic of or associated with persons who are mentally deranged: an insane laugh; insane babbling.
c. Intended for use by such persons: an insane asylum.
2. Having been determined to be in a condition that meets the legal definition of insanity.
3. Immoderate; wild: insane jealousy.
4. Very foolish; absurd: took insane risks behind the wheel.

[Latin īnsānus : in-, not; see in-1 + sānus, sane, healthy.]

in·sane′ly adv.
in·sane′ness n.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.insaneness - obsolete terms for legal insanityinsaneness - obsolete terms for legal insanity  
insanity - relatively permanent disorder of the mind


Serious mental illness or disorder impairing a person's capacity to function normally and safely:
Psychiatry: mania.
Psychology: aberration, alienation.
References in periodicals archive ?
Live telly is like heightened real life - it teeters on the brink of being out-of-control insaneness but we just keep it reined in.
This lumen has its origin with them from the light of heaven, which, when it falls into their insaneness, that is, into falsities and lusts, is turned into such [a lumen].