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lock up - 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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phrasal verb
Word Forms
present tense
I/you/we/theylock up
he/she/itlocks up
present participlelocking up
past tenselocked up
past participlelocked up
Related words
  1. 1
    [intransitive/transitive] to lock all the doors and windows of a building so that no one can get in

    I locked up and went to bed.

    The last person to leave locks up the shop.

  2. 2
    [transitive] same as lock away

    The documents were locked up.

  3. 3
    [transitive] same as lock away

    He was locked up for 12 years for armed robbery.

  4. 4
    [intransitive] to invest your money in something, so that it is not available for you to spend
    lock up in:

    There are vast sums of money locked up in pension funds.

See also main entry: lock


a rainbow produced when water droplets in the air reflect light from the moon rather than the sun

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a way of doing business that involves recruiting large numbers of people who work for themselves using the company's platform, as used by companies such as Uber, Deliveroo and the like

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