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open 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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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.

phrasal verb
Word Forms
present tense
I/you/we/theyopen up
he/she/itopens up
present participleopening up
past tenseopened up
past participleopened up
Related words
  1. 1
    [intransitive/transitive] to open a locked door, container, or building

    He opens up the drugstore every morning.

    Open up! This is the police!

  2. 2
    [intransitive] to talk more about your personal feelings and experiences
    open up to:

    It’s taken a few months, but Katy is now starting to open up to me.

  3. 3
    [intransitive/transitive] if something opens up or you open it up, it opens from a folded position so that you can see its shape

    Look, the rose buds are beginning to open up.

  4. 4
    [intransitive/transitive] if a discussion opens up, or if you open it up, it becomes more general or starts to include more subjects

    I think we need to open up the discussion and ask members of the audience for their opinions.

  5. 6
    [intransitive/transitive] to create a new opportunity or possibility

    New markets are opening up every day.

  6. 7
    [intransitive/transitive] to create a difference between the people or groups involved in something

    The issue of immigration has opened up deep divisions within the party.

    The Braves have opened up a three game lead over the second-place team.

  7. 8
    [intransitive] to start shooting a gun

    He opened up on the crowd with an automatic rifle.

    Synonyms and related words
  8. 9
    [transitive] open someone up informal to cut into someone’s body for medical reasons

    When they opened her up they found a huge tumor.

  9. 10
    [intransitive/transitive] same as open

    Donald wants to retire and open up a bookstore.

  10. 11
    [intransitive/transitive] if something opens up, or if you open it up, it opens from a folded position so that you can see its shape

    The rose buds are beginning to open up.

    She opened her umbrella up at the first drops of rain.

See also main entry: open
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a form of location that involves the underwater detonation of a bomb which causes sound waves that are picked up by ships

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