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back - definition and synonyms


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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.



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verb back pronunciation in American English /bæk/
Word Forms
present tense
present participlebacking
past tensebacked
past participlebacked
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  1. 1
    [transitive] to give support to a person, organization, or plan, making them more likely to succeed

    Both main parties are backing these proposals.

    back someone on something:

    We’ll back you all the way on this one!

    1. a.
      [usually passive] to make an order or request more effective by threatening to do something if people do not do what you want

      Schools need to have clear rules on bullying, backed by a system of punishments.

  2. 2
    [intransitive/transitive] to move backward, or to make someone move backward
    back into/onto/out of etc.:

    She backed out of the room carrying a tray.

    He backed me into a corner at the party.

    1. a.
  3. 3
    [transitive] to bet (=risk money) that a particular person or animal will win a race or competition

    I’m backing France to win the championship.

    Synonyms and related words
  4. 4
    [transitive] [often passive] music to play or sing the music that goes with the main singer or musician’s performance

    Manilow was backed by a full orchestra.

  5. 5
    [transitive] [always passive] if a place is backed by something, it has something at the back of it or directly behind it


to fall over forwards so that your face hits the ground or another surface

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the activity of exploring abandoned buildings and other manmade structures

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