'impractical' originates from the prefix 'im-' meaning 'not' and the word 'practical', which comes from the Latin 'practicus', meaning 'fit for action'.

'practicus' transformed into the Old French word 'practique', and eventually became the modern English word 'practical'.

Initially, it meant 'fit for action', but over time it evolved into its current meaning of 'not suitable for practical use'.