Did you know?

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

flat - definition and synonyms


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.



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.

adjective flat pronunciation in American English /flæt/
Word Forms
  • Facebook
  • Twitter
  1. 1
    level and parallel to the ground

    The building has a flat roof.

    You need a flat surface to work on.

    1. a.
      smooth on the surface, with no lumps or slopes

      The farmland is very flat.

      a firm flat stomach

      Synonyms and related words
    2. b.
      thin and wide and not curving inward or outward

      a monitor with a flat screen

      She put the fruit on a large flat plate.

  2. 2
    stretched out or lying on a surface

    Stand with your feet flat on the floor.

    flat on your back:

    She was flat on her back asleep.

  3. 3
    a flat rate or amount is the same in all situations, so that you do not pay more or less

    The bank charges a flat fee of $15 for money transfers.

  4. 6
    a flat tire does not have enough air in it
  5. 7
    mainly British a flat battery does not have enough power left in it
  6. 8
    a flat drink has lost its bubbles of gas, so that it does not taste good
  7. 9
    flat shoes have very low heels or no heels
  8. 10
    spoken in a voice that does not go up and down. This word is often used for describing the speech of people from a particular region.
  9. 11
    appearing as a line on a graph that does not go up or down, showing no activity or variety
  10. 13
    music a B flat, E flat etc. is a musical note that is one halftone lower than B, E etc.

sea lion

in an online conversation, repeatedly asking a person questions which suggest that you are interested in what they are talking about, but are actually intended to annoy them

BuzzWord Article

Word of the Day


to teach someone

Open Dictionary


an electric skateboard

add a word


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