'undesignated' originates from the prefix 'un-' meaning 'not' and the word 'designate' from Latin 'designatus', past participle of 'designare', meaning 'to mark out'.

'designatus' transformed into the English word 'designate', and with the addition of the prefix 'un-', it became 'undesignated'.

Initially, 'designate' meant 'to mark out or appoint', and 'undesignated' evolved to mean 'not marked out or appointed'.