'unpressured' originates from the prefix 'un-' meaning 'not' and the word 'pressured', which comes from the Latin word 'pressura', meaning 'to press'.

'pressura' transformed into the Old French word 'presseure', and eventually became the modern English word 'pressure'. The prefix 'un-' was added to form 'unpressured'.

Initially, 'pressura' meant 'to press', but over time, 'pressure' evolved to mean 'the exertion of force'. 'Unpressured' retains the meaning of 'not under force or stress'.