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day - definition and synonyms

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noun     day pronunciation in British English
Word Forms
  1. 1
    [countable] one of the periods of time that a week is divided into, equal to 24 hours

    We’re going away for five days.

    The animals are kept inside for 14 hours a day.

    24 hours a day (=during the whole of the day and night):

    The shop is open 24 hours a day.

    1. a.
      [countable] [usually singular] the period of time when you are awake and doing things
      every day:

      You should try to go for a walk every day.

      all day (long):

      What do you do at home all day?

      a bad/hard/long day (=a difficult or unpleasant day):

      She came home exhausted after a hard day at the office.

      a day off (=a day when you do not work):

      I’ve got a day off next week.

      a day out (=a day when you go out somewhere for fun or enjoyment):

      All children enjoy a day out at the fair.

  2. 2
    [countable/uncountable] the period of time when it is light outside

    There was not enough of the day left to finish the game.

    during the day:

    The restaurant is only open during the day.

    by day (=during the day):

    By day he is a banker, but by night he sings in a club.

  3. 3
    [singular] a period of time in the past or future

    We look forward to the day when nuclear weapons will no longer exist.

    the day will/may/might come (when):

    The day may come when our air becomes too polluted to breathe.

  4. 4


    [plural] a period of time when you are doing a particular thing, or when something is happening or is successful

    I think my days as a footballer are coming to an end.

    That was back in the days of the horse and cart.

    the early days of something:

    She became famous in the early days of television.

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