lunacy

play
noun lu·na·cy \ˈlü-nə-sē\

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 and Etymology of lunacy

lunatic


First Known Use: 1541


LUNACY Defined for English Language Learners

lunacy

play
noun lu·na·cy \ˈlü-nə-sē\

Definition of lunacy for English Language Learners

  • : extreme foolishness

  • : something that is very foolish

  • : extreme mental illness


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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