Definition of lunacy in English:

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Pronunciation: /ˈluːnəsi/

noun (plural lunacies)

[mass noun]
1The state of being a lunatic; insanity (not in technical use): it has been suggested that originality demands a degree of lunacy
More example sentences
  • Either he wanted to make me delirious with jealousy over her vile decadence or simply get my certified opinion concerning her degree of lunacy.
  • It does not supply the answer in the situation of an infant, a person under lunacy or overseas.
  • This goes beyond mere bullying and descends into paranoid - and hypocritical - lunacy.
insanity, madness, mental illness, derangement, dementia, dementedness, insaneness, loss of reason, unsoundness of mind, mental instability, mania, frenzy, psychosis
informal craziness
1.1Extreme folly or eccentricity: such an economic policy would be sheer lunacy
More example sentences
  • Writing from the perspective of an intelligent though lonely and bewildered child, he uses incisive humour to expose the lunacies, vagaries and hypocrisies of traditional and alternative belief systems.
  • Even those who never believed that the lunacies of the seventies and early eighties had been entirely eradicated - evidence to the contrary has been accumulating for several years - did not predict the recent chain reaction of violence.
  • This little masterpiece has its lunacies (why is it necessary for the memories to be restaged and turned into film clips?) and its limitations.


Mid 16th century (originally referring to insanity of an intermittent kind attributed to changes of the moon): from lunatic + -acy.

For editors and proofreaders

Line breaks: lu¦nacy

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