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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.