View synonyms for mad



[ mad ]


comparative: madder [mad, -er],superlative: maddest [mad, -ist].
  1. mentally disturbed; deranged; insane; demented.

    Synonyms: crazy, crazed, maniacal, lunatic

  2. enraged; greatly provoked or irritated; angry.

    Synonyms: irate, wrathful, furious

  3. (of animals)
    1. abnormally furious; ferocious:

      a mad bull.

    2. affected with rabies; rabid:

      a mad dog.

  4. extremely foolish or unwise; imprudent; irrational:

    a mad scheme to invade France.

    Synonyms: unsafe, perilous, dangerous, ill-advised

    Antonyms: safe, sound, practical, sensible

  5. wildly excited or confused; frantic:

    mad haste.

    Synonyms: frenzied

  6. overcome by desire, eagerness, enthusiasm, etc.; excessively or uncontrollably fond; infatuated:

    He's mad about the opera.

  7. wildly lively and merry; enjoyably hilarious:

    to have a mad time at the Mardi Gras.

  8. (of wind, storms, etc.) furious in violence:

    A mad gale swept across the channel.

  9. Slang. much or many:

    Mad props for getting this organization off the ground.


  1. Slang. very; extremely:

    It's mad hot in this car.

verb (used with object)

, mad·ded, mad·ding.
  1. Archaic. to make mad.

verb (used without object)

, mad·ded, mad·ding.
  1. Archaic. to be, become, or act mad.



[ mad ]



abbreviation for

  1. madam.



/ mæd /


  1. mentally deranged; insane
  2. senseless; foolish

    a mad idea

  3. informal.
    often foll by at angry; resentful
  4. foll byabout, on, or over; often postpositive wildly enthusiastic (about) or fond (of)

    mad about football


  5. extremely excited or confused; frantic

    a mad rush

  6. temporarily overpowered by violent reactions, emotions, etc

    mad with grief

  7. of animals
    1. unusually ferocious

      a mad buffalo

    2. afflicted with rabies
  8. like mad informal.
    with great energy, enthusiasm, or haste; wildly
  9. mad as a hatter
    crazily eccentric


  1. archaic.
    to make or become mad; act or cause to act as if mad



/ mæd /

acronym for

  1. mutual assured destruction: a theory of nuclear deterrence whereby each side in a conflict has the capacity to destroy the other in retaliation for a nuclear attack
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Usage Note

Mad meaning “enraged, angry” has been used since 1400, and this sense is a very common one. Because some teachers and usage critics insist that the only correct meaning of mad is “mentally disturbed, insane,” mad is often replaced by angry in formal contexts: The president is angry at Congress for overriding his veto.
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Derived Forms

  • ˈmaddish, adjective
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Other Words From

  • half-mad adjective
  • half-mad·ly adverb
  • half-mad·ness noun
  • qua·si-mad adjective
  • qua·si-mad·ly adverb
  • un·mad adjective
  • un·mad·ded adjective
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Word History and Origins

Origin of mad1

First recorded before 900; Middle English mad (adjective), madden (intransitive verb, derivative of the adjective); Old English gemǣd “made mad,” past participle of gemǣdan (unrecorded) “to make mad,” akin to gemād “mad, foolish”; cognate with Old Saxon gemēd, Old High German gimeit “foolish”
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Word History and Origins

Origin of mad1

Old English gemǣded, past participle of gemǣdan to render insane; related to gemād insane, and to Old High German gimeit silly, crazy, Old Norse meitha to hurt, damage
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Idioms and Phrases

  1. have a mad on, Informal. to be angry for a period of time; be in a bad mood:

    The last time he had a mad on, it lasted for days.

  2. like mad, Informal. with great haste, impulsiveness, energy, or enthusiasm:

    She ran like mad to catch the bus.

  3. mad as a hatter, completely insane.

More idioms and phrases containing mad

  • crazy (mad) about
  • drive someone crazy (mad)
  • hopping mad
  • like crazy (mad)
  • stark raving mad
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Synonym Study

Mad, crazy, insane are used to characterize wildly impractical or foolish ideas, actions, etc. Mad suggests senselessness and excess: The scheme of buying the bridge was absolutely mad. In informal usage, crazy suggests recklessness and impracticality: a crazy young couple. Insane is used with some opprobrium to express unsoundness and possible harmfulness: The new traffic system is simply insane.
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Example Sentences

When he has called the police in the past, they have not responded, or responded “mad late.”

From righteous fury to faux indignation, everything we got mad about in 2014—and how outrage has taken over our lives.

The house decays around Amelia and Samuel, their world narrows and becomes mad, undealable with.

We fight over their ownership and control, as if reality were a resource as scarce as the water and oil in Mad Max.

This year's shockers: no Amy Poehler, nothing for 'Mad Men,' and a whole lot of love for virgins and transgenders.

Then she won, and went half mad with the joy and excitement, but the joy didn't last long.

Mankind, mad with the energy of activity, would be seen to pursue the fleeing phantom of insatiable desire.

Irene's been down to the train to meet you three times and she's sure fighting mad by this time.

Your mad career generally ended in a crowd and a free fight of confetti.

Some who would face a mad bull coolly enough spring with disgust from a cockroach or a centipede.


Definitions and idiom definitions from Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.