The Collaborative International Dictionary of English v.0.48:

Confederacy \Con*fed"er*a*cy\, n.; pl. Confederacies. [From
   Confederate, a.]
   1. A league or compact between two or more persons, bodies of
      men, or states, for mutual support or common action;
      alliance.
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            The friendships of the world are oft
            Confederacies in vice or leagues of pleasure.
                                                  --Addison.
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            He hath heard of our confederacy.     --Shak.
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            Virginia promoted a confederacy.      --Bancroft.
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   2. The persons, bodies, states, or nations united by a
      league; a confederation.
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            The Grecian common wealth, . . . the most heroic
            confederacy that ever existed.        --Harris.
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            Virgil has a whole confederacy against him.
                                                  --Dryden.
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   3. (Law) A combination of two or more persons to commit an
      unlawful act, or to do a lawful act by unlawful means. See
      Conspiracy.

   Syn: League; compact; alliance; association; union;
        combination; confederation.
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