The defence pleaded insanity, but the defendant was found guilty and sentenced.
2. uncountable noun
If you describe a decision or an action as insanity, you think it is very foolish.
[disapproval]
It was a period of collective insanity, of legalized murder and mayhem.
...the final financial insanity of the 1980s.
Synonyms: stupidity, folly, lunacy, irresponsibility More Synonyms of insanity
insanity in British English
(ɪnˈsænɪtɪ)
nounWord forms: plural-ties
1.
relatively permanent disorder of the mind; state or condition of being insane
2. law
a defect of reason as a result of mental illness, such that a defendant does not know what he or she is doing or that it is wrong
3.
utter folly; stupidity
insanity in American English
(ɪnˈsænəti)
nounWord forms: pluralinˈsanities
1.
the state of being insane; mental illness or derangement, usually excluding amentia
not a technical term
2. Law
any form or degree of mental derangement or unsoundness of mind, permanent or temporary, that makes a person incapable of what is regarded legally as normal, rational conduct or judgment: it usually implies a need for hospitalization
3.
great folly; extreme senselessness
SYNONYMY NOTE: insanity, current in popular and legal language but not used technically in medicine (seedefinition above), implies mental derangement in one who formerly had mental health;, lunacy specifically suggests periodic spells of insanity, but is now most commonly usedin its extended sense of extreme folly; , dementia is the general term for an acquired mental disorder, now generally one of organicorigin, as distinguished from amentia (congenital mental deficiency); psychosis is the psychiatric term for any of various specialized mental disorders, functionalor organic, in which the personality is seriously disorganized
OPPOSITE: sanity
Word origin
L insanitas < insanus
Examples of 'insanity' in a sentence
insanity
The only defence for either man would be to plead insanity.
Times, Sunday Times (2011)
He is expected to plead insanity in a bid to avoid murder charges.
The Sun (2013)
You should have grabbed a fork and jabbed her in the bottom, then pleaded temporary insanity.
Times, Sunday Times (2012)
What terrible, collective insanity has overtaken this country?
Times, Sunday Times (2011)
It's a very curious form of collective insanity.
Times, Sunday Times (2011)
Perhaps she was overcome by the heat, or more probably it was just a moment of temporary insanity.
Times, Sunday Times (2012)
At his trial, his revolutionary defence of partial insanity succeeded and presented the government of the day with a problem.
The Sun (2011)
Sport, like life, is about mastering the art of temporary insanity.
Times, Sunday Times (2008)
A temporary insanity may ensue.
Times, Sunday Times (2014)
But I don't think the insanity defence will do his lawyers much good.
The Sun (2013)
In other languages
insanity
British English: insanity NOUN
Insanity is the state of being insane.
The film is a powerful study of a woman's descent into insanity.