Did you know?

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

knock - 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.

verb knock pronunciation in British English /nɒk/
Word Forms
present tense
present participleknocking
past tenseknocked
past participleknocked
  • Facebook
  • Twitter
  1. 1
    [intransitive/transitive] to hit something, causing damage or harm

    Mike had knocked his leg against a table.

    Synonyms and related words
    1. a.
      [transitive] to hit something and force it somewhere

      He knocked a couple of nails into the door.

      Synonyms and related words
    2. b.
      [transitive] to hit someone very hard, so that they fall or become unconscious
      knock someone to/off/over/down:

      They knocked him to the ground.

      The force was powerful enough to knock him off balance.

      knock someone unconscious:

      The driver had been knocked unconscious by the impact.

    3. c.
      [transitive] to make a hole or space in something by hitting it many times

      They knocked a hole for the doorway.

  2. 2
    [intransitive] to hit a door with your hand or a knocker so that someone inside knows you are there

    They walked up to the door and knocked loudly.

    knock on/at:

    I knocked on his door but got no reply.

  3. 3
    [intransitive] if an engine or machine knocks, it makes noises that show it is not working correctly
  4. 4
    [transitive] informal to criticize someone or something in a way that seems unfair


used to describe something which is done more carefully and over a longer period of time …

BuzzWord Article

Open Dictionary


the practice of giving birth in the presence of several friends and relatives

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