Definition of insanity
- the insanity of violence
- His comments were pure insanity.
- the insanities of modern life
She was found not guilty by reason of insanity.
His friends thought his decision to quit his job was pure insanity.
Please, no more violence. It's time to stop this insanity.
the insanities of modern life
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'insanity.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
An oft-quoted bon mot (frequently attributed to Albert Einstein, Benjamin Franklin, or a number of other people who probably never said it) is that insanity may be defined as “doing the same thing over and over and expecting different results.” While the job of lexicographers might be easier if they were allowed to use witty sayings instead of precise definitions, such belletristic labors are not within their purview. The straight facts about insanity are these: it has been in use in English since the late 16th century, for the first two hundred years or so carrying only the literal meaning “the condition of being mentally deranged.” In the 19th century it began to take on a looser sense, “extreme folly or unreasonableness.” In modern usage, insanity may be found in both senses: you may tell your brother that trying to skateboard while holding onto a car is "insanity" (in which case you mean that it is extremely foolish) or encounter the stricter original meaning in such contexts as insanity plea.
absurdity, asininity, balminess, brainlessness, craziness, daftness, dippiness, dottiness, fatuity, fatuousness, folly, foolishness, imbecility, inanity, lunacy, madness, nonsensicalness, nuttiness, preposterousness, senselessness, silliness, simplicity, wackiness, witlessness, zaniness;
denseness, dim-wittedness, doltishness, dopiness, dullness (also dulness), dumbness, feeblemindedness, idiocy, mindlessness, oafishness, obtuseness, simplemindedness, simpleness, slowness, stupidity, stupidness, vacuity;
: severe mental illness : the condition of being insane
: something that is very foolish or unreasonable
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