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1. The condition of being mentally deranged.
2. Great folly: It was sheer madness to attempt the drive during a blizzard.
3. Enthusiasm; excitement: the madness of Mardi Gras.
4. Archaic Fury; rage.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. insanity; lunacy
2. extreme anger, excitement, or foolishness
3. (Veterinary Science) a nontechnical word for rabies
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈmæd nɪs)

1. the state of being mad; insanity.
2. senseless folly.
3. frenzy; rage.
4. intense excitement or hilarity.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


  • ire, rage, fury - Ire suggests greater intensity than anger, rage suggests loss of self-control, and fury is destructive rage verging on madness.
  • mania - Based on a Greek word meaning "madness," ultimately from an Indo-European root for "mind."
  • rage - Traces back to Latin rabia, an alteration of rabies, meaning "fury, madness."
  • woodness - Madness or insanity, from Old English wood, "out of one's mind."
Farlex Trivia Dictionary. © 2012 Farlex, Inc. All rights reserved.


  1. As crazy as a baboon chasing shit around a tree —American colloquialism
  2. As crazy as a loon —American colloquialism

    Popular variations include “Crazy as bats” and “Crazy as a bed bug,” the latter said to make its first appearance in Ernest Hemingway’s For Whom the Bell Tolls.

  3. Crazy as owl shit —Pat Conroy
  4. As mad as a brush —Julia O’Faolain
  5. As mad as a March hare —English phrase

    Even though Lewis Carroll didn’t coin the phrase as many people think, its appearance in Alice in Wonderland probably contributed towards its common and continued usage to describe irrationality. The same is true of “Mad as a hatter” which originally alluded to the symptoms of madness by workers in the hat industry caused by exposure to chemicals.

  6. As mad as a serpent —Carolyn See, New York Times/Hers, July 3, 1986
  7. As nutty as a fruitcake —American colloquialism

    In vogue since around 1935 this has seeded such twists as “You’re as nutty as a Mars bar” (Tom Robbins) and “Nuttier than a Hershey bar with almonds” (Ed Mc Bain). Departing from the candy and cake comparisons altogether, there’s “As nutty as a squirrel’s nest” (Mike Sommer).

Similes Dictionary, 1st Edition. © 1988 The Gale Group, Inc. All rights reserved.


You should be careful which words you use to refer to someone who has an abnormal mental condition. The adjectives mad, insane, crazy, demented, and deranged, and the nouns lunatic, maniac, madman, and spastic are usually avoided nowadays in serious speech and writing because they are thought to be offensive.

Instead, you can say that someone is mentally ill. If their condition is less severe, you can say that they are mentally disturbed or unbalanced, or that they have psychological problems.

At least ninety percent of the men and women who kill themselves are mentally ill. institution for mentally disturbed children.
...the area of the jail reserved for women with psychological problems.
Collins COBUILD English Usage © HarperCollins Publishers 1992, 2004, 2011, 2012
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.madness - obsolete terms for legal insanitymadness - obsolete terms for legal insanity  
insanity - relatively permanent disorder of the mind
2.madness - an acute viral disease of the nervous system of warm-blooded animals (usually transmitted by the bite of a rabid animal)madness - an acute viral disease of the nervous system of warm-blooded animals (usually transmitted by the bite of a rabid animal); rabies is fatal if the virus reaches the brain
zoonosis, zoonotic disease - an animal disease that can be transmitted to humans
3.madness - a feeling of intense angermadness - a feeling of intense anger; "hell hath no fury like a woman scorned"; "his face turned red with rage"
anger, ire, choler - a strong emotion; a feeling that is oriented toward some real or supposed grievance
wrath - intense anger (usually on an epic scale)
lividity - a state of fury so great the face becomes discolored
4.madness - the quality of being rash and foolish; "trying to drive through a blizzard is the height of folly"; "adjusting to an insane society is total foolishness"
stupidity - a poor ability to understand or to profit from experience
5.madness - unrestrained excitement or enthusiasm; "poetry is a sort of divine madness"
ebullience, enthusiasm, exuberance - overflowing with eager enjoyment or approval
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


3. frenzy, riot, furore, uproar, abandon, excitement, agitation, intoxication, unrestraint The country was in a state of madness
"We are all born mad. Some remain so" [Samuel Beckett Waiting for Godot]
"Though this be madness, yet there's method in't" [William Shakespeare Hamlet]
"O! that way madness lies; let me shun that" [William Shakespeare King Lear]
"What is a more irrefutable proof of madness than an inability to have a doubt?" [Sir Peter Ustinov Dear Me]
Collins Thesaurus of the English Language – Complete and Unabridged 2nd Edition. 2002 © HarperCollins Publishers 1995, 2002


1. Serious mental illness or disorder impairing a person's capacity to function normally and safely:
Psychiatry: mania.
Psychology: aberration, alienation.
The American Heritage® Roget's Thesaurus. Copyright © 2013, 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
정신 이상
sự điên rồ


[ˈmædnɪs] N
1. (= mental illness) → locura f, demencia f
2. (= foolishness) → locura f
it would be sheer madness to continuesería una auténtica locura seguir
it's madness!¡es una locura!
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005


[ˈmædnəs] nfolie f
It's absolute madness → C'est de la pure folie.
in a moment of madness → dans un moment de folie
it would be madness to do ... → ce serait de la folie de faire ...
It is madness for the police to remain unarmed
BUT C'est de la folie que la police ne soit toujours pas armée.
Collins English/French Electronic Resource. © HarperCollins Publishers 2005


nWahnsinn m; it’s sheer madness!das ist heller or reiner Wahnsinn!; what madness!das ist doch Wahnsinn!
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007


[ˈmædnɪs] npazzia, follia
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995


(mӕd) adjective
1. mentally disturbed or insane. Ophelia went mad; You must be mad.
2. (sometimes with at or with) very angry. She was mad at me for losing my keys.
3. (with about) having a great liking or desire for. I'm just mad about Harry.
ˈmadly adverb
ˈmadness noun
ˈmadden verb
to make mad or very angry. The animal was maddened by the pain.
ˈmaddening adjective
likely to cause anger. maddening delays.
ˈmaddeningly adverb
ˈmadmanplural ˈmadmen: feminine ˈmadwoman plural ˈmadwomen noun
a person who is insane. He drove/fought like a madman.
mad ˈcow disease noun
a fatal disease of cattle, which can affect also humans who eat meat from infected cattle.
like mad
wildly, desperately, very quickly etc. struggling/trying/running like mad.
Kernerman English Multilingual Dictionary © 2006-2013 K Dictionaries Ltd.


جُنُونٌ šílenství vanvid Wahnsinn τρέλα locura hulluus folie ludost pazzia 狂気 정신 이상 krankzinnigheid galskap szaleństwo loucura сумасшествие galenskap ความวิกลจริต çılgınlık sự điên rồ 疯狂
Multilingual Translator © HarperCollins Publishers 2009
References in classic literature ?
Returning to the proceedings of him of the Rueful Countenance when he found himself alone, the history says that when Don Quixote had completed the performance of the somersaults or capers, naked from the waist down and clothed from the waist up, and saw that Sancho had gone off without waiting to see any more crazy feats, he climbed up to the top of a high rock, and there set himself to consider what he had several times before considered without ever coming to any conclusion on the point, namely whether it would be better and more to his purpose to imitate the outrageous madness of Roland, or the melancholy madness of Amadis; and communing with himself he said:
I knew that she could not live long; but the thought that before her death she might give birth to some ill-fated being, destined to hand down madness to its offspring, determined me.
Hence poetry implies either a happy gift of nature or a strain of madness. In the one case a man can take the mould of any character; in the other, he is lifted out of his proper self.
Madness in its first stage--monomania--is a lack of proportion.
They think me mad --Starbuck does; but I'm demoniac, I am madness maddened!
Ah, ye brethren, that God whom I created was human work and human madness, like all the Gods!
(The treatment given to Malvolio was the regular one for madmen; it was thought that madness was due to an evil spirit, which must be driven out by cruelty.) Make sure of the story and characters as before.
For think, in all thy sadness, What road our griefs may take; Whose brain reflect our madness, Or whom our terrors shake.
You had better see him, for his madness is amusing."
So she fled and took up her abode in the haunted glen; and this was the nature of her madness, that whenever she saw children, and more especially girl children, a longing came upon her to kill them as her own had been killed.
He imagined that his superior held him in contempt, and so he chafed and fumed inwardly until one evening his madness became suddenly homicidal.