LUNACY Synonyms: 123 Similar and Opposite Words

lunacy

noun

ˈlü-nə-sē

Definition of lunacy

as in insanity

a foolish act or idea you want to sneak into the building after the alarm is set—what lunacy!

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Antonyms & Near Antonyms

as in dementia

a serious mental disorder that prevents one from living a safe and normal life the judge ruled that the lunacy of the accused made him incompetent to stand trial

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as in madness

lack of good sense or judgment was it desperation or lunacy that caused him to quit his job and move to California without any plan for what to do when he got there?

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Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of lunacy After all, there’s ample lunacy to be found on the left and the right these days. — Clarence Page, Chicago Tribune, 30 Mar. 2026 Once upon a time, the idea of a baseball team allowing most of its games to be broadcast on television was lunacy. — Ken Sugiura, AJC.com, 24 Feb. 2026 Because it’s invariably attached to the idea of some kind of lunacy. — Zack Sharf, Variety, 3 Nov. 2025 Because it's invariably attached to the idea of some kind of lunacy. — Mekishana Pierre, Entertainment Weekly, 3 Nov. 2025 See All Example Sentences for lunacy

Recent Examples of Synonyms for lunacy

Noun

Massachusetts law states that a person committed after a successful insanity defense can be recommitted over and over again, each time for a one-year period.

— Aysha Bagchi, USA Today, 28 Aug. 2026
Doing the same thing over again and expecting a different result is what some people call insanity.

— Ryan Canfield OutKick, FOXNews.com, 28 Aug. 2026

Definition of insanity

Noun

Sleep, for instance, isn’t downtime but active maintenance, when the brain flushes out cellular waste in ways that may help stave off dementia.

— Andrea Gawrylewski, Scientific American, 1 Sep. 2026
Developed by researchers in the US, the remarkable new treatment could one day be used to treat patients in advanced stages of dementia by restoring the brain’s ability to recover from ongoing neurodegeneration.

— Mike McRae August 30, New Atlas, 31 Aug. 2026

Definition of dementia

Noun

Can a squad of scientists (including Kurt Russell) fight off madness and mayhem before the Thing overtakes them all?

— Beatrice Verhoeven, HollywoodReporter, 25 Aug. 2026
This week the madness leaps from the stage to the screen as Stamptown premieres its first Netflix special Tuesday.

— Deputy Entertainment, Los Angeles Times, 25 Aug. 2026

Definition of madness

Noun

It’s been a classic staple over decades of British comedy, which from Basil Fawlty to David Brent has rejoiced in puncturing pomposity to reveal idiocy and incompetence.

— Alex Ritman, Variety, 7 Aug. 2026
The school board’s radical idiocy does not negate the state’s obligation to think about the longer haul — specifically, the structurally unbalanced budgets facing Chicago Public Schools as far as the eye can see.

— The Editorial Board, Chicago Tribune, 7 Aug. 2026

Definition of idiocy

Noun

The roughly 25-acre farm is also home to a reproduction of the Salem Village Meeting House, the site of many early hearings about the Salem witchcraft hysteria.

— Nicholas DeRenzo, Travel + Leisure, 25 Aug. 2026
Russia has rejected all accusations of espionage, portraying them as part of anti-Russian hysteria.

— Brady Knox, The Washington Examiner, 21 Aug. 2026

Definition of hysteria

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lunacies

lunacy

lunatic

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“Lunacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/lunacy. Accessed 2 Sep. 2026.

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Synonyms of lunacy

noun

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