ENGLISH
REFERENCE

period

n. · adj. · interj.
US //ˈpɪɹiəd// UK //pˈiəɹɪəd// pe·ri·od
  1. 1 a length of time (n.)
    A1 Beginner

    a specific amount of time.

    a generic interval or duration of time.

    Example

    The doctor told him to rest for a short period after the surgery.

    Example

    The company experienced a period of rapid expansion followed by several years of consolidation and restructuring.
  2. 2 school lesson (n.)
    A2 Elementary

    one of the parts that a school day is divided into.

    a division of the academic day allocated to a specific subject or activity.

    Example

    We have double maths in the first period on Monday mornings.

    Example

    The bell rang to signal the end of the third period, sending hundreds of students into the narrow corridors.
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  1. 3 punctuation mark (n.)
    A2 Elementary American English

    the small dot (.) used at the end of a sentence.

    the punctuation mark used to indicate the end of a declarative sentence or an abbreviation.

    Example

    Don't forget to put a period at the end of every sentence.

    Example

    The editor noted that several sentences were missing a closing period, which made the paragraph difficult to parse.

    Usage

    Called a 'full stop' in British English.

    Teacher's tip

    Learners should be aware that 'period' is the standard term in North America, while 'full stop' is used in the UK and Australia.
    • full stop
  2. 4 menstruation (n.)
    B1 Intermediate Medicine

    the monthly flow of blood from a woman's body.

    the monthly discharge of blood and mucosal tissue from the uterus; menstruation.

    Example

    She often gets bad headaches just before her period starts.

    Example

    The patient reported irregular periods and significant abdominal discomfort during the first two days of her cycle.
  3. 5 historical era (n.)
    B1 Intermediate

    a particular time in history.

    a distinct portion of history characterised by specific events, cultures, or developments.

    Example

    The Victorian period saw many changes in how people lived and worked.

    Example

    Archaeologists are currently excavating a site that dates back to the early Roman period in Britain.
  4. 6 sports division (n.)
    B1 Intermediate Sport

    one of the parts that a game is divided into.

    one of the fixed intervals into which a sporting match is divided.

    Example

    The home team scored three goals in the second period of the hockey game.

    Example

    After a scoreless first period, the coach made several tactical adjustments to increase the team's offensive pressure.
  5. 7 scientific/math cycle (n.)
    C1 Advanced Technical Science

    the time it takes for something to happen again and again.

    the interval of time or space after which a periodic function or physical motion repeats itself.

    Example

    The period of the earth's rotation is approximately twenty-four hours.

    Example

    The physicist calculated the orbital period of the satellite to ensure it would remain in a geostationary position.
  6. 8 chemistry table row (n.)
    C1 Advanced Technical Chemistry

    a horizontal row of elements in the periodic table.

    a horizontal row in the periodic table of elements, representing the filling of an electron shell.

    Example

    Elements in the same period have the same number of electron shells.

    Example

    As you move from left to right across a period, the atomic radius typically decreases due to the increasing nuclear charge.
  7. 9 historical style (adj.)
    B2 Upper Intermediate

    made to look like it belongs to a specific time in the past.

    belonging to or characteristic of a particular historical time, especially regarding furniture, clothing, or architecture.

    Example

    The actors wore beautiful period costumes for the movie about the 1920s.

    Example

    The hotel was decorated with period furniture to maintain the atmosphere of the original eighteenth-century manor house.
  8. 10 that is final (interj.)
    B2 Upper Intermediate Informal American English

    used to say that you will not discuss something anymore.

    used for emphasis at the end of a statement to indicate that it is final and no further discussion is permitted.

    Example

    I am not going to that party, period.

    Example

    The manager told the staff that safety regulations were non-negotiable, period.
    • full stop
    • end of story
Origin

From Middle English periode, from Middle French periode, from Medieval Latin periodus, from Ancient Greek περίοδος (períodos, “circuit, orbit, a recurring interval of time, path around”), from περι- (peri-, “around”) + ὁδός (hodós, “way”). Displaced native Middle English tide (“interval, period, season”), from Old English tīd (“time, period, season”), as well as Middle English elde (“age, period”), from Old English ieldu (“age, period of time”).

Word family

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