inclusion

UK: /ɪnˈkluːʒ^ən/ US: /ɪnˈkluʒən/ ,(in klo̅o̅′zhən)

WordReference Random House Unabridged Dictionary of American English © 2025

in•clu•sion  (in klo̅o̅′zhən), n. 

1. the act of including.
2. the state of being included.
3. something that is included.
4. Cell Biology [Biol.] a body suspended in the cytoplasm, as a granule.
5. Mineralogy a solid body or a body of gas or liquid enclosed within the mass of a mineral.
6. Geology, Rocks [Petrog.] xenolith.
7. Mathematics, Philosophy [Logic, Math.] the relationship between two sets when the second is a subset of the first.

• Latin inclūsiōn- (stem of inclūsiō) a shutting in, equivalent. to inclūs(us) (see incluse) + -iōn- -ion
• 1590–1600; 1945–50 for def. 7;

Collins Concise English Dictionary © HarperCollins Publishers::

inclusion / ɪnˈkluːʒən/ noun

1. the act of including or the state of being included
2. something included

WordReference Random House Learner's Dictionary of American English © 2025

in•clude /ɪnˈklud/   v. [~ + object] , -clud•ed, -clud•ing. 

1. to contain or have as part of a whole:
   [not: be + ~-ing] The meal includes dessert and coffee.
2. to place (something) in a category:
   Whom would you include in your list?

in•clu•sion /ɪnˈkluʒən/  n. [uncountable]

WordReference Random House Unabridged Dictionary of American English © 2025

in•clude  (in klo̅o̅d′), v.t., -clud•ed, -clud•ing. 

1. to contain, as a whole does parts or any part or element:
   The package includes the computer, program, disks, and a manual.
2. to place in an aggregate, class, category, or the like.
3. to contain as a subordinate element;
   involve as a factor.

• Latin inclūdere to shut in, equivalent. to in- in-² + -clūdere, combining form of claudere to shut (compare close)
• late Middle English 1375–1425

in•clud′a•ble, in•clud′i•ble, adj. 
Synonyms

• 1. embody.
  Include, comprehend, comprise, embrace imply containing parts of a whole. To include is to contain as a part or member, or among the parts and members, of a whole:
  The list includes many new names.
  To comprehend is to have within the limits, scope, or range of references, as either a part or the whole number of items concerned:
  The plan comprehends several projects.
  To comprise is to consist of, as the various parts serving to make up the whole:
  This genus comprises 50 species.
  Embrace emphasizes the extent or assortment of that which is included:
  The report embraces a great variety of subjects.

Antonyms

• 1. exclude, preclude.