'unschedule' originates from the prefix 'un-' meaning 'not' or 'reverse' and the word 'schedule' from Old French 'cedule', meaning 'a slip of paper'.

'schedule' evolved from the Old French word 'cedule', which was derived from the Latin 'schedula', meaning 'a small strip of paper'.

Initially, 'schedule' referred to a written list or plan, and 'unschedule' evolved to mean the removal of an item from such a list.