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secret - definition and synonyms

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noun [countable]     secret pronunciation in British English
Word Forms
  1. 1
    a piece of information that is known by only a small number of people, and is deliberately not told to other people

    I can’t tell you what she said – it’s a secret.

    Your secret is safe with me (=I will not tell anyone).

    The secret is out (=everyone knows about it).

    It cannot remain a secret much longer.

    keep a secret (=not tell anyone):

    Can you promise to keep a secret?

    keep something a secret (from someone):

    Mandela kept his work a secret from the prison authorities.

    let someone in on a secret (=tell someone a secret):

    Listen, I’ll let you in on a little secret.

  2. 2
    [usually plural] something that cannot be explained or that is difficult to understand

    What secrets of the universe will the new telescope reveal?

  3. 3
    a particular way of achieving something

    She always looks so slim – I wish I knew her secret.

    The secret is always to warm the pot before putting in the tea.

    secret of:

    The secret of our success is having highly skilled staff.



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

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