union
C1Formal to neutral. Common in political, academic, technical (maths), and industrial discourse.
Definition
Meaning
The act of joining two or more things together to form a single unit, or the state of being so joined.
An organization, group, or association formed by people with a common purpose, such as a trade union or a political union like the European Union; the unity of a country, especially one formed from separate states; the set-theoretic operation that combines all elements of two or more sets; a marriage.
Linguistics
Semantic Notes
The word carries strong connotations of solidarity, cooperation, and collective strength. In politics, it can imply federalism or confederation. In industrial contexts, it is almost synonymous with 'trade union' or 'labour union'.
Dialectal Variation
British vs American Usage
Differences
In the UK, 'Union' often specifically refers to a trade union. 'The Union' can refer to the UK itself (the union of England, Scotland, Wales, and Northern Ireland). In the US, 'union' is heavily associated with 'labour union'. 'The Union' historically refers to the federal government/northern states during the Civil War.
Connotations
Both share core connotations of solidarity. In the US political context, 'union' has a strong patriotic connotation of national unity. In the UK, it can be politically charged regarding the union of the constituent countries.
Frequency
Equally frequent in both varieties. The specific referents (e.g., Trades Union Congress vs. AFL-CIO) differ.
Vocabulary
Collocations
Grammar
Valency Patterns
[the] union of X and YX in union with Yto form/join/dissolve a uniona union between X and YVocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “in perfect union”
- “a marriage union”
- “more perfect union”
- “the Union Jack (British flag)”
Usage
Context Usage
Business
Refers to a merger or acquisition (e.g., 'the union of the two companies'), or to labour relations ('negotiating with the union').
Academic
Used in political science (e.g., 'fiscal union'), history ('the Union of the Crowns'), and mathematics ('the union of two sets').
Everyday
Most commonly refers to a trade union or a student union building. Also used for marriage.
Technical
In mathematics and computer science, denotes the set operation '∪'. In engineering, can refer to a pipe fitting ('pipe union').
Examples
By Part of Speech
verb
British English
- The two factions voted to unionise.
- The workers decided to unionise for better rights.
American English
- The two factions voted to unionize.
- The workers decided to unionize for better rights.
adverb
British English
- Not commonly used as an adverb.
- N/A
American English
- Not commonly used as an adverb.
- N/A
adjective
British English
- The union representative addressed the meeting.
- They are in a unionised workplace.
American English
- The union representative addressed the meeting.
- They are in a unionized workplace.
Examples
By CEFR Level
- The students met in the union building.
- My father is a member of a trade union.
- The union of the two companies created a market leader.
- They worked in union to complete the project on time.
- The European Union has expanded several times since its inception.
- The union leader called for a strike vote after the breakdown of negotiations.
- The country was grappling with the tension between states' rights and a strong federal union.
- In set theory, the union of A and B contains all elements that are in A, in B, or in both.
Learning
Memory Aids
Mnemonic
Think of 'ONION'—an onion is made of many layers united into one bulb. 'UNION' is many parts united into one whole.
Conceptual Metaphor
UNION IS WHOLENESS (e.g., 'a more perfect union'); UNION IS STRENGTH (e.g., 'in union there is strength'); MARRIAGE IS A UNION.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid confusing 'union' (союз, объединение) with 'university' (университет).
- The Russian 'профсоюз' maps directly to 'trade union' or simply 'union'.
- In set theory, 'union' is 'объединение', not 'союз'.
- The political 'Soviet Union' is a proper name; do not use 'union' generically for all historical federations.
Common Mistakes
- Misspelling as 'unioun'.
- Using 'union' for a simple 'meeting' or 'gathering'.
- Incorrect article: 'He is in union' (wrong) vs. 'He is in a union' (correct).
- Confusing 'union' (n) with 'unite' (v).
Practice
Quiz
In which context does 'union' NOT typically refer to an organisation of workers?
FAQ
Frequently Asked Questions
No. While a common meaning is 'trade union', it also refers to political entities (the EU), the act of joining, and a mathematical operation.
'Union' refers to the state of being joined or the organisation itself. 'Unity' refers to the state of being in harmony or agreement, often more abstract (e.g., national unity).
Not directly. The verb is 'unite'. 'Unionise/unionize' is a verb meaning 'to form a trade union'.
It represents the union of the kingdoms of England, Scotland, and (later) Ireland. 'Jack' refers to a small flag flown on a ship.
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