Dictionary.com
Thesaurus.com
Jump To:
  • union
    union
    noun
    the act of uniting two or more things.
  • Union
    Union
    noun
    a township in NE New Jersey.
Synonyms
Trivia Time
What group of professionals does the prominent labor union SAG-AFTRA represent?

union

1 American  
[yoon-yuhn] / ˈjun jən /

noun

  • unions
    plural
  1. the act of uniting two or more things.

    Antonyms:
    division, separation
  2. the state of being united.

    Antonyms:
    division, separation
  3. something formed by uniting two or more things; combination.

  4. a number of persons, states, etc., joined or associated together for some common purpose.

    student union; credit union.

  5. a group of states or nations united into one political body, as that of the American colonies at the time of the Revolution, that of England and Scotland in 1707, or that of Great Britain and Ireland in 1801.

  6. the Union. the United States.

    The Union defeated the Confederacy in 1865.

  7. a device emblematic of union, used in a flag or ensign, sometimes occupying the upper corner next to the staff or occupying the entire field.

  8. the act of uniting or an instance of being united in marriage or sexual intercourse.

    an ideal union; an illicit union.

    Synonyms:
    liaison, wedlock
  9. an organization of workers; a labor union.

  10. Mathematics.

    1. Also called join, logical sum, sum. the set consisting of elements each of which is in at least one of two or more given sets. ∪

    2. the least upper bound of two elements in a lattice.

  11. the process or result of merging or integration of disjoined, severed, or fractured elements, as the healing of a wound or broken bone, the growing together of the parts in a plant graft, the fusion of pieces in a welding process, or the like.

  12. the junction or location at which the merging process has taken place.

  13. any of various contrivances for connecting parts of machinery or the like.

  14. Textiles.

    1. a fabric of two kinds of yarn.

    2. a yarn of two or more fibers.


Union 2 American  
[yoon-yuhn] / ˈjun jən /

noun

  1. a township in NE New Jersey.

  2. a city in NW South Carolina.


union 1 British  
/ ˈjuːnjən /

noun

  1. the condition of being united, the act of uniting, or a conjunction formed by such an act

  2. an association, alliance, or confederation of individuals or groups for a common purpose, esp political

  3. agreement or harmony

  4. short for trade union

  5. the act or state of marriage or sexual intercourse

  6. a device on a flag representing union, such as another flag depicted in the top left corner

  7. a device for coupling or linking parts, such as pipes

  8. (often capital)

    1. an association of students at a university or college formed to look after the students' interests, provide facilities for recreation, etc

    2. the building or buildings housing the facilities of such an organization

  9. Also called: join. maths a set containing all members of two given sets. Symbol: ⋃, as in A⋃B

    1. a number of parishes united for the administration of poor relief

    2. a workhouse supported by such a combination

  10. textiles a piece of cloth or fabric consisting of two different kinds of yarn

  11. (modifier) of or related to a union, esp a trade union

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Union 2 British  
/ ˈjuːnjən /

noun

    1. the union of England and Wales from 1543

    2. the union of the English and Scottish crowns (1603–1707)

    3. the union of England and Scotland from 1707

    4. the political union of Great Britain and Ireland (1801–1920)

    5. the union of Great Britain and Northern Ireland from 1920

    1. the United States of America

    2. the northern states of the US during the Civil War

    3. ( as modifier )

      Union supporters

  1. short for the Union of South Africa

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

union Scientific  
/ yo̅o̅n′yən /
  1. A set whose members belong to at least one of a group of two or more given sets. The union of the sets {1,2,3} and {3,4,5} is the set {1,2,3,4,5}, and the union of the sets {6,7} and {11,12,13} is the set {6,7,11,12,13}. The symbol for union is .

  2. Compare intersection


Union Cultural  
  1. The United States; especially the northern states during the Civil War, which remained with the original United States government. (Compare Confederacy.)


Usage

What is a union? A union is a group of workers for a particular organization or industry who come together for collective bargaining with their employers. Labor unions and trade unions often work closely with employers to maintain the rights, wages, benefits, and liberties of the unionized workers, peacefully protesting when necessary. Broadly, a union is a combination of people or things. Any time two or more things come together physically, emotionally, or politically, they are said to be in a union. It could be as simple as the union of peanut butter and jelly on a sandwich. Two more important unions are a marriage and a civil union, which is a lesser alternative for a marriage. While a civil union doesn’t offer all of the rights and protections in the law that a marriage does, it is recognized by most governments as a permanent relationship with some rights and protections. A union might also refer to a larger group of people joined together for a common purpose besides labor issues, such as a credit union (an alternative to a traditional bank) and a student union, a place set aside on some college and university campuses for student activities. Example: The union of the companies went smoothly and everyone is benefitting.

Synonym Usage

Union, unity agree in referring to a oneness, either created by putting together, or by being undivided. A union is a state of being united, a combination, as the result of joining two or more things into one: to promote the union between two families; the Union of England and Scotland. Unity is the state or inherent quality of being one, single, individual, and indivisible (often as a consequence of union): to find unity in diversity; to give unity to a work of art. See alliance.

Other Word Forms

Derived Forms

Inflected Forms

Nouns


Etymology

Origin of union

First recorded in 1400–50; late Middle English, from Middle French, from Late Latin ūniōn-, stem of ūniō, from Latin ūn(us) “one” + -iō -ion


Explanation

A union is things coming together, or uniting, to make one. When the thirteen colonies that became the United States came together, they formed a union. Marriage is another kind of union. Workers come together to form trade unions so that together they can have a stronger voice negotiating with their employer. The word famously occurs in the Preamble (the introduction) to the United States Constitution: "We the people of the United States, in Order to form a more perfect Union...do ordain and establish this Constitution...." You may recognize the Latin root unum in union, as in e pluribus unum "from many, one," the motto on the seal of the United States.

Keep Reading on Vocabulary.com

Vocabulary lists containing union

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Members of Napo, the probation service union, voted to refuse overtime from 23 November - and could take strike action should the union "deem that option to be necessary".

From BBC ● Nov. 13, 2026

Dan Osborn, a former union leader and Navy veteran, first ran for Senate in 2024, losing to the GOP incumbent by nearly 7 points.

From Slate ● Nov. 13, 2026

A labor union, which was trying to organize T-Mobile, filed an unfair labor practice allegation.

From The Wall Street Journal ● Nov. 12, 2026

The union pointed to a motion written by Councilmember Heather Hutt and Councilmember Park in May, which sought to explore giving firefighters extra pension credit for mandatory overtime.

From Los Angeles Times ● Nov. 12, 2026

Often used for trade union meetings, the huge domed theater had been modified for the match.

From "Endgame" by Frank Brady

If its status is confirmed, it would join the five dwarf planets currently recognized by the International Astronomical Union: Pluto, Ceres, Eris, Haumea and Makemake.

From Science Daily ● Nov. 14, 2026

Shut out of the markets and its bonds downgraded to junk, Greece was forced to seek assistance from the European Union and the International Monetary Fund.

From The Wall Street Journal ● Nov. 14, 2026

But the American Civil Liberties Union and other immigration rights advocates said the right of individuals to seek asylum was recognized in U.S. law and could not be abolished.

From Los Angeles Times ● Nov. 13, 2026

Lee Gelernt, an attorney with the American Civil Liberties Union, one of groups which brought the case, welcomed the opportunity to present arguments to the Supreme Court.

From Barron's ● Nov. 13, 2026

That afternoon the leaders of the United States, Great Britain, France, and the Soviet Union walked into a large room in Élysée Palace.

From "Fallout: Spies, Superbombs, and the Ultimate Cold War Showdown" by Steve Sheinkin

Other sports unions have used it to gain leverage in labor negotiations, but for baseball it would be a first.

From The Wall Street Journal ● Nov. 14, 2026

But unions say it is still difficult for junior freelance workers, who often find their income unstable and unpredictable, to speak up.

From BBC ● Nov. 14, 2026

Opponents, from the farmers, shippers and other firms that rely on rail service to the unions that represent rail workers, say a giant, powerful railroad would slack on service and drive up costs.

From The Wall Street Journal ● Nov. 13, 2026

The company wants to implement a "productivity offensive" to drive down costs, including an increase in working hours for no extra pay, but here too there has been no agreement with the unions.

From Barron's ● Nov. 12, 2026

Generations later, the female descendants of those unions should still have mitochondria identical to the mitochondria of their female Botocudo ancestors.

From "1491" by Charles C. Mann

Random Word

Spin the wheel and learn a new word!

Get a word


Vocabulary.com logo
by dictionary.com

Look it up. Learn it forever.

Remember new words for good with VocabTrainer. Expand your vocabulary effortlessly with personalized learning tools that adapt to your goals.

Take me to Vocabulary.com