We found 8 dictionaries that define the word customs unions:

General (6 matching dictionaries)

1. customs unions: Merriam-Webster
2. customs unions: Collins English Dictionary
3. customs unions: Vocabulary.com
4. customs unions: Wiktionary
5. Customs unions: Wikipedia, the Free Encyclopedia
6. customs unions: TheFreeDictionary.com

Business (1 matching dictionary)

7. customs unions: Financial dictionary

Computing (1 matching dictionary)

8. customs unions: Encyclopedia

(Note: See customs_union as well.)

Definitions from Wiktionary (customs union) ▸ noun:  A type of trade bloc which is composed of a free trade area with a common external tariff. ▸ Also see customs_union ▸ Words similar to customs unions ▸ Usage examples for customs unions ▸ Idioms related to customs unions ▸ Wikipedia articles (New!) ▸ Words that often appear near customs unions ▸ Rhymes of customs unions ▸ Invented words related to customs unions