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see insanityinsanity,
mental disorder of such severity as to render its victim incapable of managing his affairs or of conforming to social standards. Today, the term insanity is used chiefly in criminal law, to denote mental aberrations or defects that may relieve a person from the legal
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an obsolete term for somnambulism, derived from ancient notions concerning the moon’s effect on the mind.


(formerly) any severe mental illness
References in classic literature ?
Result, three lunacy cases: Dartworthy selling out his mine for one-tenth its value; the poor woman sacrificing her respectability and sheltered nook in society to flee with him in an open boat down the Yukon; and Colonel Walthstone, breathing murder and destruction, taking out after them in another open boat.
You talk of the lunacy of the Pyncheons; is it contagious?
There was still further proof of Drowne's lunacy, if credit were due to the rumor that he had been seen kneeling at the feet of the oaken lady, and gazing with a lover's passionate ardor into the face that his own hands had created.
Besides, old Soap-Suds was sick enough at not getting his peerage last year; he'd sack me by wire if I lost him it with such lunacy as this.
We have written about the lunacy of school-children unionism on many occasions in this space, joking that before long the kids would be demanding the abolition of exams.
EVE MUIRHEAD has criticised the lunacy preventing her Olympic stars defending their world crown next month.
Synopsis: "Sets, Lights, and Lunacy, A Stage Designer's Adventures on Broadway and in Opera", chronicles the bright sunset of 'The Great White Way.
A Trade in Lunacy THE SHOP FRONT THEATRE TALKING Birds has collaborated with the University of Warwick's Centre for the History of Medicine to produce a theatrical examination of 18th century private asylums.
There was a moment when I thought a deal might happen, but it was total lunacy to turn up at QPR because the deal was not agreed.
The book also looks at the work of the Commissioners in Lunacy (1845-1913), the exposes these cases produced, and the greater risk faced by those with money or property.
Their clothing boutique Lunacy has been named among Vogue's top 100 shops outside of London - the only Welsh store to make the prestigious list.
In the nineteenth century the trinity of property, lunacy and divorce laws operated inter-connectedly and conspired with male-defined notions of insanity to provide an alternative for husbands who could not divorce their wives: a "madhouse divorce".