'alliance' originates from Old French, specifically the word 'aliance,' where 'ali-' meant 'to bind' and '-ance' was a suffix indicating action or process.

'aliance' transformed into the Middle English word 'alliaunce,' and eventually became the modern English word 'alliance'.

Initially, it meant 'a binding agreement,' but over time it evolved into its current meaning of 'a union for mutual benefit'.