Union generally refers to two or more things joined into one, such as an organization of multiple people or organizations, multiple objections combined into one, and so on. The term may mean:

In politics

• The Union, referring to the federation that is the United States
  • The Union (American Civil War), the states that did not declare their secession
  • The Union Army, the army of the United States in the Civil War
  • National Union Party (United States), forerunner of the United States Republican Party during the 1864 election
• Act of Union, one of several acts by the English Parliament
  • United Kingdom, the constitutional result of that legislation
• African Union, an inter-governmental organization in Africa
• Union of South American Nations
• European Union, a supranational and inter-governmental organization in Europe
• Government of India, known officially as the Union Government
• Personal union, a group of separate, independent states that share the same monarch
• Political union, a type of state composed of smaller states
• Real union, an intermediate step between personal and political union of states
• Soviet Union, Union of Soviet Socialist Republics
• State of the Union Address annual speech by the President of the United States
• The Union (political coalition) (l'Unione), a twenty-first century Italian political coalition
• Unionist Party (Canada), known when in power as the Union Government
• Trade union, labor union, employment

In sports and entertainment

• Unión de Santa Fe, Argentine professional football club
• R. Union Saint-Gilloise, Belgian professional football club
• Club Atlético Unión de Sunchales, lower league Argentine football club
• Unión Magdalena a Colombian professional football club
• Union, a group of professional wrestlers in opposition to the Corporate Ministry in the World Wrestling Federation
• The supporters' club of the A-League football side Melbourne Victory
• Rugby Union
• Union (album), a 1991 album by the musical group Yes
• Union (band), an American heavy metal band
• Union (comic), set in the Star Wars universe
• Union of Solar Energy and Free Nations, a fictional organization in anime Mobile Suit Gundam 00
• Union (comics), a character published by Wildstorm
• "Union", a song by Avail from their 2000 album One Wrench
• "Union", a song by the Black Eyed Peas ft Sting from their album Monkey Business

In education

The term student union can be used in either of two senses:

• Students' union, a student organization at many colleges and universities dedicated to student governance (not common in USA, see below)
• Student activity center, a building that typically hosts a "union" of student services (e.g., food service, health facilities, lounges) at such institutions (also know as a "student center" or "student commons")

In the United States, the phrase more commonly refers to the building. The phrase "student government" or "student senate" is usually used when referring to the subject of the "Students' union" article.

• Union College, a college for which the principal campus sits in Schenectady, New York
• Union College (Kentucky), a college in Kentucky
• Union Institute & University, a non-traditional educational institution
• Union Public Schools, a public school system in Tulsa, Oklahoma
• Union Theological College, a college in Northern Ireland
• Union Theological Seminary in the City of New York, an ecumenical Christian seminary in New York City, New York
• Union Theological Seminary & Presbyterian School of Christian Education, a Christian seminary in Richmond, Virginia
• Union University, a Baptist college in Tennessee

In transportation

• Union Railroad, any of several railroad companies
• Union (ship), a ship sunk in Fiji in 1804

In tradesmanship

• Union (electrical), a term sometimes used for a butt connector used to splice wires
• Union (hardware), a term sometimes used for a standoff that serves as an elongated nut
• Union (plumbing), a pipe fitting

In numismatics

• Union (coinage), a US gold coin that was worth $100 face value, it was never made because it would only be circulated among banks.

In mathematics and computer science

• Union (set theory)
• Union (SQL), an operator that combines the result of two SQL SELECT queries into a single result table
• Union (computer science), a data structure that stores several types of data in the same location.
• Union mount, a way to access separate file system directories as if they were but one.

In geography

• Union Station, any of several depots at which two or more railway, subway, or bus lines merge
  • Union subway station in Toronto, named for the adjacent railway station
• Union, Alabama
• Union, Connecticut
• Union, Illinois
• Union, Iowa
• Union, Kentucky
• Union, Maine
• Union, Mississippi
• Union, Missouri
• Union, Nebraska
• Union Township, Hunterdon County, New Jersey
• Union Township, Union County, New Jersey
• Union, New York
• Union, Ohio
• Union, Oregon
• Union, South Carolina
• Union, West Virginia
• Union, Wisconsin
• Union, Saint Vincent
• Union, Grenadines
• Unión, Paraguay
• Union City, California
• Union City, Georgia
• Union City, Indiana
• Union City, Michigan
• Union City, New Jersey
• Union City, Ohio
• Union City, Pennsylvania
• Union City, Tennessee
• Union County, Arkansas
• Union County, Georgia
• Union County, Illinois
• Union County, Indiana
• Union County, Iowa
• Union County, Kentucky
• Union County, Mississippi
• Union County, New Jersey
• Union County, New Mexico
• Union County, North Carolina
• Union County, Ohio
• Union County, Oregon
• Union County, Pennsylvania
• Union County, South Carolina
• Union County, South Dakota
• Union County, Tennessee
• Union Township, Michigan
• Union Township, New Jersey
• Union Township, Pennsylvania
• Mount Union, Iowa
• Uniontown
• Unionville
• Union Beach, New Jersey
• Union Grove, Alabama
• Union Hill, Illinois
• Union Park, Florida
• Union Parish, Louisiana
• Union Springs, Alabama
• Union Springs, New York
• West Union, Iowa

As a surname

• Gabrielle Union, an American actress

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