union Definition

union
noun

1a. The action or an act of uniting two or more things;

Thesaurus: junction, unification, uniting, joining, coupling, annexation, congregation, merging, fusion, synthesis, incorporation; Antonym: alienation, separation, severance.
1b. The state of being united.
2. A united whole.
3. surgery.
The growing together in healing of the parts of a broken bone, sides of a wound, etc.
4a. formal
Marriage; the state of wedlock;
Thesaurus: marriage, wedlock, matrimony, cohabitation, match; Antonym: divorce, estrangement, legal separation.
4b. formal
Sexual intercourse.
5. An association, confederation, etc of people or groups for a common (especially political) purpose.

Thesaurus: group, organization, federation, association, society, confederacy, league.
6. Agreement or harmony.
7. A league or association, especially a trade union.
8a. A device representative of union on a flag;
8b. The same device used separately as a flag, such as the Union Jack.
9. A device that connects one thing with another, especially a connecting part for pipes, etc.
10a. An organization concerned with the interests and welfare of the students in a college, university, etc;

Form: Union (also)
10b. The building that houses such an organization, often also the site of canteen and recreational facilities, etc.

Form: Union (also)
11. A textile fabric made from more than one kind of fibre.
12a. math.
(symbol È) a set² (noun 2) comprising all the members (but no others) of two or more smaller sets;
12b. math.
(symbol È) the operation of forming such a set. See also intersection sense 5.
13. historical
In 19c England: a number of parishes united for the administration of the poor laws.
14. In the Indian subcontinent: a local administrative unit made up of several villages.

Etymology: 15c: from French, from Latin unio, unionis oneness or unity, from Latin unus one.