Synonyms for Confederacy (same or very similar meaning)
WordNet sense 1 (the southern states that seceded from the United States in 1861):
dixieland, south, dixie, Confederate States, Confederate States of America
WordNet sense 2 (a union of political organizations):
confederation, federation
WordNet sense 3 (a group of conspirators banded together to achieve some harmful or illegal purpose):
conspiracy
From the ODE community, based on WordNet
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