noun
lunacy
LOO-nuh-see
Lunacy (noun) means Madness or insanity, especially of a kind once believed to come and go with the phases of the moon. Example: “His wild rants were dismissed as lunacy by everyone who knew him.”
noun
1
Madness or insanity, especially of a kind once believed to come and go with the phases of the moon.
"His wild rants were dismissed as lunacy by everyone who knew him."
2
Something reckless or deeply misguided, without necessarily involving actual mental illness.
"Driving in that storm would be pure lunacy."
"Spending the whole budget on one advert was lunacy."
How to use lunacy
Learner’s notesIn plain EnglishMadness — either literal insanity or, more commonly today, just a wildly reckless or foolish idea.
Common pairings
sheer lunacy
an act of lunacy
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Word forms
- Plural
- lunacies
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His wild rants were dismissed as _____ by everyone who knew him.
Etymology
From lunatic + the noun-forming suffix -cy; ultimately from Latin luna ("moon"), reflecting the old belief that madness waxed and waned with the moon.
Synonyms
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Related words
Rhymes for lunacy
See all rhymes for lunacy →Frequently asked questions
What does “lunacy” mean?
The word “lunacy” means madness or insanity, especially of a kind once believed to come and go with the phases of the moon. In plain terms, madness — either literal insanity or, more commonly today, just a wildly reckless or foolish idea.
How do you pronounce “lunacy”?
“Lunacy” is pronounced LOO-nuh-see (/ˈluː.nə.si/ in IPA).
How do you use “lunacy” in a sentence?
Here is “lunacy” used in a sentence: “His wild rants were dismissed as lunacy by everyone who knew him.”
What is another word for “lunacy”?
Words with a similar meaning to “lunacy” include insanity, madness, craziness and craze.
What part of speech is “lunacy”?
“Lunacy” is a noun.
Where does the word “lunacy” come from?
The word “lunacy” comes from Latin. From lunatic + the noun-forming suffix -cy; ultimately from Latin luna ("moon"), reflecting the old belief that madness waxed and waned with the moon.
How many meanings does “lunacy” have?
“Lunacy” has 2 distinct senses listed in this dictionary. The most common is: madness or insanity, especially of a kind once believed to come and go with the phases of the moon.
