1. the act of joining or combining two or more things into one
2. a group of states or countries joined together under one government
3. an organization of workers formed to protect their rights and interests

Examples

• The union of the two companies created a powerful corporation.
• The European Union consists of 27 member countries.
• The workers formed a union to negotiate better wages.
• The couple celebrated their union with a small ceremony.
• The union between art and technology produced amazing results.
• She joined the teachers’ union after getting her first job.
• The union of hydrogen and oxygen creates water.