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know - definition and synonyms


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verb [never progressive] know pronunciation in American English /noʊ/
Word Forms
present tense
present participleknowing
past tenseknew
past participleknown
  1. 1
    [intransitive/transitive] to have learned or found out about something
    If you don’t know the answer, just guess.
    How do you know my name?
    “Have they arrived yet?” “I don’t know.”
    know (that): I knew she wasn’t really happy.
    know what/where/how etc.: I don’t know where the money’s coming from.
    know if: I need to know if she’s made a decision yet.
    know something about someone/something: I don’t know anything about it.
    know something for sure/for certain/for a fact: We know for a fact that the fire was started deliberately.
    know something from experience: We know from experience that unemployment makes the problem worse.
    Synonyms and related words
    1. a.
      [intransitive/transitive] to realize or understand something
      None of us really knew what had gone wrong.
      Synonyms and related words
    2. b.
      [transitive] [often passive] used about things that most people think or believe are true
      The ancient city is known to have existed in the region.
      know someone/something to do something: Some drugs are known to cause damage to unborn children.
      know someone/something to be something: The pilots were experienced and known to be very competent.
      Synonyms and related words
  2. 2
    [transitive] to be familiar with someone, because you have met them or because you are friends
    Some of you may know Ivan already.
    She had known Nancy for years.
    I felt I hardly knew my father.
    1. a.
      to be familiar with a process or system
      Do you know this program?
      You know the rules.
      Synonyms and related words
    2. b.
      to be able to speak a language
      Do you know any Spanish?
    3. c.
      to be familiar with a place, because you have been there
      Do you know Rome well?
      Synonyms and related words
    4. d.
      to be familiar with things such as books, music, or art
      Do you know Beethoven’s Ninth Symphony?
      Synonyms and related words
  3. 3
    [transitive] to use a particular name for someone or something
    know someone/something as something: The place was known as Boot Hill.
    know someone/something by something: They know all their professors by their first names.
  4. 4
    [transitive] to remember or recognize someone because of a particular skill or quality that they have
    know someone as/for something: He was best known as a painter.
    We know her mostly for her poetry.
    Synonyms and related words
  5. 5
    [transitive] to experience something
    It was the only comfort and warmth she had ever known.
    have never known something: He had never known anything like this intense feeling.
    have never known someone (to) do something: I’ve never known her to tell a joke.
  6. 6
    [transitive] to have learned a poem, story, or song, so that you can say it or sing it
    I still know the words to some of these hymns.
    Synonyms and related words
  7. 7
    [intransitive/transitive] to feel certain about something
    know (that): She knew it was Steven before she picked up the phone.
    Synonyms and related words
  8. 8
    [transitive] to recognize someone or something
    It was Henry; I would have known him anywhere.


phrasal verbs



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