The word "lunacy" in English means: Extreme foolishness or crazy behavior., A state of being mentally ill; insanity..
The phonetic transcription of "lunacy" is /ˈluːnəsi/ in British English and /ˈluːnəsi/ in American English. Click the 🔊 button to hear both pronunciations.
Synonyms for "lunacy": madness, insanity, folly.
Example usage of "lunacy": "His idea was sheer lunacy.". More examples on the page.