'Insanity' definitions:

Definition of 'insanity'

From: WordNet
noun
Relatively permanent disorder of the mind [ant: saneness, sanity]

Definition of 'Insanity'

From: GCIDE
  • Insanity \In*san"i*ty\, n. [L. insanitas unsoundness; cf. insania insanity, F. insanite.]
  • 1. The state of being insane; unsoundness or derangement of mind; madness; lunacy. [1913 Webster]
  • All power of fancy over reason is a degree of insanity. --Johnson. [1913 Webster]
  • Without grace The heart's insanity admits no cure. --Cowper. [1913 Webster]
  • 2. (Law) Such a mental condition, as, either from the existence of delusions, or from incapacity to distinguish between right and wrong, with regard to any matter under action, does away with individual responsibility.
  • Syn: Insanity, Lunacy, Madness, Derangement, Alienation, Aberration, Mania, Delirium, Frenzy, Monomania, Dementia.
  • Usage: Insanity is the generic term for all such diseases; lunacy has now an equal extent of meaning, though once used to denote periodical insanity; madness has the same extent, though originally referring to the rage created by the disease; derangement, alienation, are popular terms for insanity; delirium, mania, and frenzy denote excited states of the disease; dementia denotes the loss of mental power by this means; monomania is insanity upon a single subject. [1913 Webster]

Synonyms of 'insanity'

From: Moby Thesaurus