'Confederacy' originates from Latin, specifically the word 'confoederatio,' where 'con-' meant 'together' and 'foedus' meant 'league or treaty.'

'Confoederatio' transformed into the Old French word 'confederacie,' and eventually became the modern English word 'Confederacy' through Middle English.

Initially, it meant 'a league or treaty,' but over time it evolved into its current meaning of 'a union of states or groups for a common purpose.'