1. The act of including or the state of being included.
2. Something included.
3. A solid, liquid, or gaseous foreign body enclosed in a mineral or rock.
4. A nonliving mass, such as a droplet of fat, in the cytoplasm of a cell.
5. Computers A logical operation that assumes the second statement of a pair is true if the first one is true.
[Latin inclūsiō, inclūsiōn-, from inclūsus, past participle of inclūdere, to enclose; see INCLUDE.]
in·clusion·ar′y (-zhə-nĕr′ē) adj.
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