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REFERENCE

expansion

n.
US //ɪkˈspænʃən// UK //ɛkspˈænʃən// ex·pan·sion
  1. 1 growth in size or scope (n.)
    B2 Upper Intermediate

    the act of becoming bigger or covering more area.

    the action of becoming larger or more extensive in physical size or conceptual scope.

    Example

    The rapid expansion of the city has led to more traffic on the roads.

    Example

    The rapid expansion of urban areas often outpaces the development of necessary infrastructure, leading to significant logistical challenges for local governments.
  2. 2 business or economic growth (n.)
    B2 Upper Intermediate Economics

    when a company or an economy grows and becomes more successful.

    a period of economic growth or the process of a business increasing its market presence and operations.

    Example

    The company is planning an expansion into the European market next year.

    Example

    Economists predicted a period of sustained expansion following the implementation of the new trade agreement and the reduction of interest rates.
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  1. 3 physical increase in volume (n.)
    C1 Advanced Technical Science

    the increase in the volume of a substance, often caused by heat.

    the increase in volume of a substance, typically resulting from a change in temperature or pressure.

    Example

    The expansion of the metal in the heat caused the door to get stuck.

    Example

    Engineers must account for the thermal expansion of steel beams when designing bridges to prevent structural failure during extreme summer temperatures.
  2. 4 added content or detail (n.)
    B2 Upper Intermediate Computing

    a new part added to something, like a game or a book, to make it longer or more complete.

    the addition of further detail to a narrative or the release of supplementary content for an existing software product or game.

    Example

    I bought the new expansion for my favourite board game yesterday.

    Example

    The studio released a digital expansion that introduced three new playable regions and a revamped combat system to the original title.
  3. 5 spelling out an abbreviation (n.)
    C1 Advanced Academic

    the full version of a word that has been shortened.

    the full, unabbreviated form of a word or phrase represented by an acronym or initialism.

    Example

    The expansion of 'NASA' is the National Aeronautics and Space Administration.

    Example

    The author provided the full expansion of every technical acronym in the appendix to ensure the text remained accessible to non-specialist readers.
    • full form
Origin

Borrowed from French expansion, from Latin expānsiō. By surface analysis, expand + -sion.

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