Did you know?

Click any word in a definition or example to find the entry for that word

mad - definition and synonyms

 
 
Close

What are red words?

90% of the time, speakers of English use just 7,500 words in speech and writing. These words appear in red, and are graded with stars. One-star words are frequent, two-star words are more frequent, and three-star words are the most frequent.

Close

ThesaurusThesaurus

Thesaurus diagram

The thesaurus of synonyms and related words is fully integrated into the dictionary. Click on the thesaurus category heading under the button in an entry to see the synonyms and related words for that meaning.

more
adjective     mad pronunciation in British English
/mæd/
Word Forms
Close
adjectivemad
comparativemadder
superlativemaddest
  1. 1
    very silly or stupid

    You’ll think I’m mad – I’ve just left my job.

    be mad to do something:

    You’re mad to spend so much money on clothes.

    1. a.
      informal tending to behave in a strange way that other people sometimes consider funny

      a mad scientist

    2. b.
      informal an offensive way for describing someone who is mentally ill

      She was completely mad.

  2. 2
    [never before noun] informal angry

    He makes me mad, the way he keeps criticizing me all the time.

    mad at/with:

    My boss is mad with me for missing the meeting.

  3. 3
    done quickly or without thinking, in a way that is badly organized

    There were people everywhere – it was all a bit mad!

    a mad rush/dash:

    It was a mad rush to get the job finished.

  4. From our crowdsourced Open Dictionary
    4
    mad as a wet hen extremely angry

    Mom will be mad as a wet hen if we don't get home soon.

    Submitted by Monnshine on 27/07/2015
  5. From our crowdsourced Open Dictionary
    5
    mad as a March hare completely crazy; irrational

    The young fellow is as mad as a March hare.

    Submitted from United Kingdom on 06/11/2015
  6. From our crowdsourced Open Dictionary
    6
    (as) mad as hell a rude phrase meaning "extremely angry"

    Your dad will be as mad as hell when he finds out you took his car.

    I will be mad as hell if he gets here late.

    Submitted by Caleb Judy from United States on 17/12/2015
quiz invitation
  • Facebook
  • Twitter
BuzzWord

webrooming

the practice of looking at a product online before going to a conventional store to buy it

BuzzWord Article

Open Dictionary

panjandrum

a person who has or claims to have a lot of influence

add a word

Blog

A must for anyone with an interest in the changing face of language. The Macmillan Dictionary blog explores English as it is spoken around the world today.

global English and language change from our blog
Macmillan learn live love play