'undamaged' originates from the prefix 'un-' meaning 'not' and the word 'damaged', which comes from Old French 'damager', meaning 'to cause loss or harm'.

'damager' transformed into the Middle English word 'damage', and eventually became the modern English word 'damaged'.

Initially, it meant 'to cause loss or harm', but over time it evolved into its current meaning of 'not harmed or spoiled'.