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back up

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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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phrasal verb
Word Forms
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present tense
I/you/we/theyback up
he/she/itbacks up
present participlebacking up
past tensebacked up
past participlebacked up

Related dictionary definitions

 
  1. 1
    [transitive] back someone up to give support to someone by telling other people that you agree with them

    If I ask for more money will you back me up?

  2. 5
    [intransitive] to move backward a short distance

    I need everyone to back up about 10 steps.

  3. 6
    [intransitive/transitive] to make a car go backward

    See if you can back up a little farther.

    back something up something:

    I'll back the car up the driveway.

  4. 7
    [intransitive] used for telling someone to return to something that was said earlier

    Back up: didn't you say they had already met?

See also main entry: back

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