lunacy: Meaning and Definition of

lu•na•cy

Pronunciation: (l'nu-sē), [key]
— pl. -cies.
  1. insanity; mental disorder.
  2. intermittent insanity, formerly believed to be related to phases of the moon.
  3. extreme foolishness or an instance of it: Her decision to resign was sheer lunacy.
  4. unsoundness of mind sufficient to incapacitate one for civil transactions.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
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