lunacy

noun

lu·​na·​cy ˈlü-nə-sē How to pronounce lunacy (audio)
plural lunacies
1
dated
b
: intermittent insanity once believed to be related to phases of the moon
2
: wild foolishness : extravagant folly
3
: a foolish act

Examples of lunacy in a Sentence

Quitting her job was lunacy. His idea was considered total lunacy.
Recent Examples on the Web
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Rudolph hopes that the time is finally right for audiences to appreciate the film’s lunacy and vision of an America whose values have gone completely out of whack. Jim Hemphill, IndieWire, 29 Oct. 2024 Like Spann, my perception is that the volume of lunacy and hostility was greater than usual. Marshall Shepherd, Forbes, 12 Oct. 2024 But legitimate criticism has often been lost in spiteful lunacy. Jay Nordlinger, National Review, 10 Oct. 2024 With all this lunacy, your show can also hit tender moments so well — like when Charles and Doreen make amends. Jim Halterman, Variety, 8 Oct. 2024 See all Example Sentences for lunacy 

Word History

Etymology

lun(atic) + -acy

First Known Use

1541, in the meaning defined at sense 1a

Time Traveler
The first known use of lunacy was in 1541

Dictionary Entries Near lunacy

Cite this Entry

“Lunacy.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lunacy. Accessed 11 Nov. 2024.

Kids Definition

lunacy

noun
lu·​na·​cy ˈlü-nə-sē How to pronounce lunacy (audio)
plural lunacies
: insanity sense 1
used chiefly in the past

Medical Definition

lunacy

noun
lu·​na·​cy ˈlü-nə-sē How to pronounce lunacy (audio)
plural lunacies
dated
: mental illness
also : intermittent mental illness once believed to be related to phases of the moon

Legal Definition

lunacy

noun
lu·​na·​cy ˈlü-nə-sē How to pronounce lunacy (audio)

More from Merriam-Webster on lunacy

Last Updated: - Updated example sentences
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