'unoriginal' originates from the prefix 'un-' meaning 'not' and the word 'original', which comes from Latin 'originalis', meaning 'pertaining to the beginning or origin'.

'originalis' transformed into the Old French word 'original', and eventually became the modern English word 'original'. The prefix 'un-' was added to form 'unoriginal'.

Initially, 'original' meant 'pertaining to the beginning', but over time, it evolved to mean 'new or novel'. 'Unoriginal' thus means lacking in novelty.