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insanity Line breaks: in|san¦ity
Pronunciation: /ɪnˈsanəti/

Definition of insanity in English:


[mass noun]
1The state of being seriously mentally ill; madness: he suffered from bouts of insanity
More example sentences
  • In practice, the effect of this strict approach has not been greatly to swell the numbers of people pleading insanity.
  • There's something about this place that breeds great madness and insanity.
  • The trial judge ruled that this was a defence of insanity, whereupon she pleaded guilty and appealed.
mental illness, mental disorder, mental derangement, madness, insaneness, dementia, dementedness, lunacy, instability, unsoundness of mind, loss of reason;
delirium, hysteria, mania, psychosis
informal craziness
archaic crazedness
1.1Extreme foolishness or irrationality: it might be pure insanity to take this loan [count noun]: the insanities of our time
More example sentences
  • But the show does capture the various insanities and absurdities of his life, and is filled with clips of his more outrageous outfits.
  • Sarcasm raises its ugly head between all your sacred rites and ceremonies, but you cling on to your methodical insanities.
  • Yet, one has to wonder how National, despite the multitude of Labour insanities, only leads by one point.


Late 16th century: from Latin insanitas, from insanus (see insane).

Definition of insanity in:

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