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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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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



an obsolete term for somnambulism, derived from ancient notions concerning the moon’s effect on the mind.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


(formerly) any severe mental illness
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
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?"
Two days have passed since that day of lunacy. What a noise and a fuss and a chattering and an uproar there was!
How should he but in desperate lunacy? Fond worldling, now his heart-blood dries with grief; His conscience kills it; and his labouring brain Begets a world of idle fantasies To over-reach the devil; but all in vain; His store of pleasures must be sauc'd with pain.
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.
This club has got me out of numerous shopping trips, allowed me to experience Saturday night Bristol in the heady disco days of the 80s, but perversely it gives me solidity from the lunacy of modern life, if only our own particular ordered, inevitable lunacy.
Pull back from brink of lunacy I'm afraid our country seems to have gone stark raving mad.
It is nothing short of lunacy on the part of the TMA.
And it just wouldn't be right to talk about our lunacy without giving just a brief nod to the lunacy across the Atlantic.
He even brazenly asserts that social justice policies are "lunacy." How can Williams, a man of color, dare to offend the legacies MLK, Malcolm X, Rosa Parks and all the other brave men and women who took to the streets, some giving their lives, seeking social justice in order to create more opportunities for people like him?
One wrote: "If this doesn't qualify for lefty lunacy..." Another agreed, adding: "Absolute lunacy.