Definition of "inclusion" in English

noun

1. (countable) An addition or annex to a group, set, or total.

   • The poem was a new inclusion in the textbook.

2. (uncountable) The act of including, i.e. adding or annexing, (something) to a group, set, or total.

   • The inclusion of the poem added value to the course.

3. (countable) Anything foreign that is included in a material.

4. (countable, mineralogy) Any material that is trapped inside a mineral during its formation, as a defect in a precious stone.

5. (cytology) A nuclear or cytoplasmic aggregate of stainable substances.

6. (histology) An object completely inside a tissue, such as epidermal inclusion cyst, a cyst in the epidermis.

7. (mathematics) A mapping where the domain is a subset of the image.

8. (obsolete) Restriction; limitation.