Definition of lunacy
1 dated a : insanity 1b : 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 of lunacy from the Web
The fruit of the lunacy starts with George and Harold (voiced with great childish glee by Kevin Hart and Thomas Middleditch), two elementary school buddies who spend more time pulling pranks than studying.
Summer is a time for love, lunacy, ass's ears, and laughs.
The bunkerlike storefront, on a quiet corner in a residential neighborhood, offers no indication of the unique lunacy within.
Blame it on the current lunacy surrounding any stock that even smells like an Internet play.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'lunacy'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Origin and Etymology of lunacy
First Known Use: 1541
Seen and Heard
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