Confederation

n. alliance, league; act of forming a league or alliance

A confederation is a group of empowered states or communities, usually created by treaty but often later adopting a common constitution. Confederations tend to be established for dealing with critical issues, such as defense, foreign affairs, foreign trade, and a common currency, with the central government being required to provide support for all members. A confederation, in modern political terms, is usually limited to a permanent union of sovereign states for common action in relation to other states.
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Noun
1. the state of being allied or confederated
(synonym) alliance
(hypernym) coalition, fusion
(derivation) confederate
2. a union of political organizations
(synonym) confederacy, federation
(hypernym) union
(hyponym) nation
(derivation) band together, confederate
3. the act of forming an alliance or confederation
(synonym) alliance
(hypernym) group action
(derivation) confederate

n. confederation, confederacy

(n.)
The parties that are confederated, considered as a unit; a confederacy.
  

(n.)
The act of confederating; a league; a compact for mutual support; alliance, particularly of princes, nations, or states.