federation
noun
POLITICS uk/ˌfedərˈeɪʃən/ us [ C ]
a group of organizations, regions, countries, etc. that have joined together to form a larger organization or government:
a federation of states/companies/trade unions, etc. The United States is a federation of 50 individual states.
[ U ]
the act of forming a federation:
He's against European federation.
the federation of states/companies/trade unions, etc. The federation of the six original Australian states took place in 1901.
See also
labor federation