'unenroll' originates from the prefix 'un-' meaning 'not' or 'reverse' and the word 'enroll' from Old French 'enroller', meaning 'to enter on a list'.

'enroller' transformed into the English word 'enroll', and with the addition of the prefix 'un-', it became 'unenroll'.

Initially, it meant 'to remove from a list', and this meaning has largely remained the same in modern usage.