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lunacy

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noun lu·na·cy \ˈlü-nə-sē\

Simple Definition of lunacy

  • : extreme foolishness

  • : something that is very foolish

  • : extreme mental illness

Source: Merriam-Webster's Learner's Dictionary

Full Definition of lunacy

plural lunacies

  1. 1 a :  insanity b :  intermittent insanity once believed to be related to phases of the moon

  2. 2 :  wild foolishness :  extravagant folly

  3. 3 :  a foolish act

Examples of lunacy in a sentence

  1. Quitting her job was lunacy.

  2. His idea was considered total lunacy.



Origin of lunacy

lunatic


First Known Use: 1541


Medical Dictionary

lunacy

play
noun lu·na·cy \ˈlü-nə-sē\

Medical Definition of lunacy

plural lunacies

  1. dated :  mental illness; also :  intermittent mental illness once believed to be related to phases of the moon




Law Dictionary

lunacy

play
noun lu·na·cy \ˈlü-nə-sē\

Legal Definition of lunacy





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