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inclusion

n.
US //ˌɪnˈkɫuʒən// UK //ɪnklˈuːʒən// in·clu·sion
  1. 1 the act of including (n.)
    B2 Upper Intermediate

    the act of making someone or something part of a group or list.

    the act of including or the state of being included within a group, set, or category.

    Example

    The inclusion of her name on the guest list made her very happy.

    Example

    The inclusion of diverse perspectives in the initial planning phase ensured that the final policy was robust and widely accepted.
  2. 2 social/educational practice (n.)
    B2 Upper Intermediate

    the practice of making sure everyone is treated fairly and has the same opportunities.

    the policy or practice of providing equal access to opportunities and resources for people who might otherwise be excluded or marginalised.

    Example

    The school has a strong policy on the inclusion of students with disabilities.

    Example

    Corporate social responsibility initiatives often focus on diversity and inclusion to foster a more equitable workplace environment.
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  1. 3 something added (n.)
    B2 Upper Intermediate

    a person or thing that is added to a group or collection.

    a person or thing that is included within a larger group, set, or total.

    Example

    The new player was a great inclusion to the team.

    Example

    The editor decided that the inclusion of the final chapter was necessary to provide a sense of closure to the narrative.
  2. 4 material defect (n.)
    C1 Advanced Technical Science

    a small piece of different material trapped inside a rock or metal.

    a solid, liquid, or gaseous foreign body enclosed within a mineral, metal, or other material.

    Example

    The diamond was cheaper because it had a small inclusion inside it.

    Example

    Geologists examine fluid inclusions within quartz crystals to determine the temperature and pressure conditions during the mineral's formation.
  3. 5 mathematical mapping (n.)
    C2 Proficiency Technical Math

    a way to show that one set of numbers fits inside another set.

    an injective function where each element of a subset is mapped to itself as an element of the containing set.

    Example

    The teacher explained the inclusion of whole numbers within the set of all integers.

    Example

    In set theory, the inclusion map provides a formal way to treat a subset as part of a larger codomain without changing the elements.
Origin

Borrowed from Latin inclusio, inclusionis, from the verb Latin inclūdō (“to shut in, enclose, insert”), from in- (“in”) + claudō (“to shut”), ultimately from Proto-Indo-European *kleh₂u- (“key, hook, nail”). By surface analysis, include + -sion. Doublet of enclosure.

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