'enlist' originates from Old French, specifically the word 'enlister,' where 'en-' meant 'in' and 'lister' meant 'to list or enroll.'

'enlister' transformed into the Middle English word 'enlisten,' and eventually became the modern English word 'enlist.'

Initially, it meant 'to enroll or register,' but over time it evolved into its current meaning of 'to join the military or a cause.'