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know - definition and synonyms

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verb [never progressive]     know pronunciation in American English
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.

    1. a.
      [intransitive/transitive] to realize or understand something

      None of us really knew what had gone wrong.

    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.

  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.

    1. a.
      to be familiar with a process or system

      Do you know this program?

      You know the rules.

    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?

    4. d.
      to be familiar with things such as books, music, or art

      Do you know Beethoven’s Ninth Symphony?

  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.

  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.

  7. 7
    [intransitive/transitive] to feel certain about something
    know (that):

    She knew it was Steven before she picked up the phone.

  8. 8
    [transitive] to recognize someone or something

    It was Henry; I would have known him anywhere.

phrasal verbs

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to manipulate someone psychologically so that they begin to question their own perceptions and memories

BuzzWord Article

Open Dictionary

Dunning-Kruger effect

the phenomenon by which an incompetent person is too incompetent to understand his own incompetence

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