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open - definition and synonyms


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verb open pronunciation in American English /ˈoʊpən/
Word Forms
present tense
present participleopening
past tenseopened
past participleopened
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  1. 1
    [transitive] to separate the edges of something, or to take off its cover so that you can see or remove what is inside
    She opened her purse and took out a lipstick.
    Can you open this jar of pickles?
    Open your books to page 25.
    1. a.
      [intransitive] if something such as a flower opens, it moves into its widest position and you can see its full shape
      Her parachute failed to open.
  2. 2
    [transitive] to move a door or window into a position that allows people or things to pass through
    Do you mind if I open a window?
    The gates at the zoo are opened at 8:45.
    1. a.
      [intransitive] if something such as a door opens, it moves into a position that allows people or things to pass through
      The elevator doors opened and two men walked out.
      open onto/into something: The kitchen door opens onto a patio.
  3. 3
    [intransitive/transitive] to move your arms or legs wide apart
    She opened her arms to hug me.
    1. a.
      to move your lips and teeth apart so that your mouth is not closed
      Open your mouth and let me look at your teeth.
    2. b.
      to move your eyelids apart so that your eyes are not closed
      I opened my eyes and looked around me.
  4. 4
    [intransitive/transitive] if a store, public building, etc. opens at a particular time, or if someone opens it, it regularly becomes available for people to visit or use at that time
    The library doesn’t open until noon today.
    I’m calling to ask when you open today.
  5. 5



    open up

    [intransitive/transitive] if a new business, building, etc. opens, or if someone opens it, it becomes available for people to use for the first time
    They decided to move to Spain and open a bar.
    The college first opened in the 1960s.
    1. a.
      [intransitive/transitive] if something that has been private or secret opens, or if someone opens it to people, it becomes available for people to visit, see, or take part in
      open something to someone: There are plans to open the Navy base to the public.
      open something to competition/inspection/scrutiny: The telecommunications market has been opened up to competition.
      open your doors/gates to someone: The farmer opens his gates to visitors during the lambing season.
    2. b.
      [intransitive] theatre, cinema if a movie or play opens, it starts being shown to the public
      Her new play has just opened on Broadway.
    3. c.
      [intransitive/transitive] if a road, telephone line, or other method of communication opens, or if someone opens it, it becomes available for people to use
      We are opening a hotline for questions about the product.
    4. d.
      [transitive] if a famous person opens a store or public building, they appear there to say that it is officially available for people to use or visit
      The actors are opening the new restaurant on Saturday.
  6. 6
    [intransitive] to begin a speech
    open with: He opened his talk with a quotation from Shakespeare.
    1. a.
      [transitive] to begin something such as a discussion or trial
      She opened the debate by summarizing her party’s position.
      open an investigation/inquiry/inquest: The police have opened an investigation into his business affairs.
    2. b.
      [transitive] to start an account with a bank
      You only need $1 to open an account with us.
    3. c.
      [intransitive] when a period of time opens, it begins
      The year opened well for the company.
      The trout fishing season opened last week.

phrasal verbs


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