'unattributed' originates from the prefix 'un-' meaning 'not' and the word 'attributed' from Latin 'attribuere,' where 'ad-' meant 'to' and 'tribuere' meant 'assign.'

'attribuere' transformed into the Old French word 'atribuer,' and eventually became the modern English word 'attribute,' with 'unattributed' forming by adding the prefix 'un-'.

Initially, it meant 'not assigned to a source,' and this meaning has largely remained the same in modern usage.