There are 2 definitions of mad in English:


Line breaks: mad

adjective (madder, maddest)

verb (mads, madding, madded)

[with object] archaic Back to top  
  • Make (someone) mad: had I but seen thy picture in this plight, it would have madded me
    More example sentences
    • A wise citizen, I know not whence, had a scold to his wife: when she brawled, he played on his drum, and by that means madded her more, because she saw that he would not be moved.
    • For Mrs. Bleecker was very wrathful, Euan, and Lana's indiscretions madded her.


go mad

informal Allow oneself to get carried away by enthusiasm or excitement: let’s go mad and splash out
More example sentences
  • The audience went mad with excitement when the elephant stepped on to the stage.
  • Seeing their fans going mad as we played was one of the highlights of our time.
  • Keegan jogs out from behind the entrance curtains to the sound of Oasis classic ‘Rock and Roll Star’ and the home fans go mad for it.
become frenzied, become uncontrollable, lose control, erupt, boil over

like mad

informal With great intensity, energy, or enthusiasm: I ran like mad
More example sentences
  • My eyes are hurting like mad, this means I will probably have a cold soon.
  • On Saturday morning every bone and muscle was hurting like mad but we still had to soldier on.
  • The two looked at each other for a second, then fired like crazy and ran like mad.
fast, furiously, as fast as possible, as fast as one's legs can carry one, hurriedly, quickly, rapidly, speedily, hastilyenergetically, enthusiastically, madly, with a will, for all one is worth, passionately, intensely, ardently, fervently
British informal , • dated like billy-o

(as) mad as a hatter

informal Completely insane: he’s indisputably a genius, but he’s also mad as a hatter
[with reference to Lewis Carroll's character the Mad Hatter in Alice's Adventures in Wonderland (1865), the allusion being to the effects of mercury poisoning from the use of mercurous nitrate in the manufacture of felt hats]
More example sentences
  • She's mad as a hatter but that bunch of loonies will love her.
  • ‘He is as mad as a hatter and in to everything,’ said friend Lesley Gill, who used to work with Brian in the Newbridge branch of Dunnes Stores.
  • As long as you temper your unrestrained approach to life with occasional periods of sanity - and do your best not to get arrested - it's completely acceptable to be as mad as a hatter.

mad keen

British informal Extremely enthusiastic: some men are mad keen on football
More example sentences
  • The Namibians are mad keen anglers and are extremely knowledgeable, competent, kind, helpful and dedicated to giving their clients the best possible trip.
  • Tony Heart is himself a mad keen angler and he works extremely hard at putting his anglers over the abundant quality fish; his spacious boat is purpose built for angling and cruises effortlessly at 14/15 knots.
  • You're mad keen on history - what's your favourite fact about London's past?


Old English gemǣd(e)d 'maddened', participial form related to gemād 'mad', of Germanic origin.

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Word of the day maelstrom
Pronunciation: ˈmālˌsträm
a powerful whirlpool in the sea

There are 2 definitions of mad in English:


Syllabification: MAD

Entry from US English dictionary


  • Mutual assured destruction.

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