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series

n.
US //ˈsɪɹiz// UK //sˈiəɹiz// se·ries
  1. 1 a sequence of events (n.)
    A2 Elementary

    a number of similar things or events that happen one after another.

    a number of things, events, or people of a similar kind or nature coming one after another.

    Example

    The police are investigating a series of robberies that happened in the city center last week.

    Example

    The sudden collapse of the bank triggered a series of financial crises across the continent, forcing governments to intervene with emergency loans.
  2. 2 TV or radio program (n.)
    A2 Elementary

    a set of television or radio programs that have the same characters or theme.

    a set of related television or radio programmes broadcast in regular installments.

    Example

    My favorite comedy series is returning for a third year this autumn.

    Example

    The documentary series explores the complex relationship between urban development and local wildlife preservation over the last fifty years.

    Usage

    The singular form is 'a series' and the plural form is 'two series'.

    Teacher's tip

    In British English, 'series' often means what Americans call a 'season'.
    Pitfall
    I watched a new serie last night.
    I watched a new series last night.

    The word 'series' is the same in both singular and plural forms. Do not remove the 's' for one show.

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  1. 3 sports matches (n.)
    B1 Intermediate Sport

    a group of games played between the same two teams.

    a set of matches played between two teams or players, often to determine an overall winner.

    Example

    The two national teams will play a five-match series starting next month.

    Example

    After losing the first two games, the team managed to win the series by securing victories in the final three matches.
  2. 4 mathematical sum (n.)
    C1 Advanced Academic Technical Math

    the sum of a group of numbers that follow a specific pattern.

    the sum of the terms of an infinite or finite sequence.

    Example

    The teacher asked us to calculate the sum of the geometric series.

    Example

    The student struggled to determine whether the infinite series converged to a specific value or diverged toward infinity.
  3. 5 biological classification (n.)
    C2 Proficiency Academic Technical Science

    a way to group living things that are very similar, below a 'genus' but above a 'species'.

    a taxonomic rank below section but above species, used to group closely related organisms.

    Example

    The botanist identified the new plant as belonging to a specific series within the oak family.

    Example

    The revision of the genus led to several species being reassigned to a different series based on recent genetic data.
Origin

Attested from the 1610s; borrowed from Latin seriēs, from serere (“to join together, bind”), ultimately from Proto-Indo-European *ser- (“to bind, put together, to line up”). Related to desert, insert, sermon, and sorcerer.

Word family

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