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day

n.
US //ˈdeɪ// UK //dˈeɪ// day
  1. 1 24-hour period (n.)
    A1 Beginner

    a period of 24 hours, usually starting from midnight.

    a standard unit of time representing one full rotation of the Earth, conventionally measured from midnight to midnight.

    Example

    There are seven days in a week and 365 days in a year.

    Example

    The contract stipulates that the goods must be delivered within ten working days of the initial purchase order.

    • twenty four hours
  2. 2 daylight hours (n.)
    A1 Beginner

    the time between when the sun rises and when it sets.

    the period of light between dawn and nightfall; the diurnal portion of the 24-hour cycle.

    Example

    The days are much longer in the summer than in the winter.

    Example

    As the winter solstice approached, the days grew noticeably shorter, leaving the villagers with only a few hours of usable light.

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  1. 3 work or school hours (n.)
    A2 Elementary

    the part of the day that you spend at your job or at school.

    the portion of a day dedicated to a specific activity, typically professional labor or education.

    Example

    I had a very busy day at the office and I am tired now.

    Example

    After a grueling day on the assembly line, the workers were eager to return home and rest before the next shift began.

  2. 4 a specific era (n.)
    B1 Intermediate

    a particular time in history or in someone's life.

    a specific period or era, often characterized by the prominence of a person, movement, or technology.

    Example

    In my grandfather's day, people didn't have mobile phones.

    Example

    The historian argued that the glory days of the empire were already fading by the time the new emperor took the throne.

  3. 5 planetary rotation (n.)
    B2 Upper Intermediate Technical Science

    the time it takes for a planet to turn around once.

    the duration of one complete rotation of a celestial body on its axis.

    Example

    A day on Mars is slightly longer than a day on Earth.

    Example

    Venus is unique in our solar system because its sidereal day is actually longer than its orbital year.

    • rotational period
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