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key - definition and synonyms


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noun [countable] key pronunciation in British English /kiː/
Word Forms
  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
    house/car keys
    key to: Where’s the key to the back door?
    Synonyms and related words
  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.
    Synonyms and related words
  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
    Synonyms and related words


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