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key - definition and synonyms


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noun [countable] key pronunciation in British English /kiː/
Word Forms
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  1. 1
    a small piece of metal used for opening or locking a door or a container, or for starting the engine of a vehicle

    I could hear someone turning the key in the lock.

    a bunch of keys

    key to:

    Where’s the key to the back door?

  2. 2
    [usually singular] the thing that will do most to help you to achieve something
    key to:

    Proper planning is the key to success.

    The key to our strength lies in our members.

  3. 3
    one of the parts that you press on a keyboard to make it produce letters, numbers etc

    Highlight the file you want and press the RETURN key.

  4. 4
    music a set of musical notes that are based on one particular note

    a major/minor key

    in the key of D sharp

  5. 5
    a list of signs and their meanings, for example a list of the signs that are used on a map, drawing etc
    1. a.
      a list of answers to the questions in a test or in a book


used to describe something which is done more carefully and over a longer period of time …

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the practice of giving birth in the presence of several friends and relatives

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