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.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.