Definition of insanity in English:

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Pronunciation: /ɪnˈsanəti/


[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
rare deliration
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.
folly, foolishness, foolhardiness, idiocy, stupidity, imbecility, asininity, lunacy, madness, silliness, senselessness, brainlessness, thoughtlessness, irrationality, illogicality, absurdity, ludicrousness, ridiculousness
informal craziness
British informal daftness


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

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Line breaks: in|san¦ity

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