'expensive' originates from Latin, specifically the word 'expensivus', where 'ex-' meant 'out' and 'pendere' meant 'to weigh or pay'.

'expensivus' transformed into the French word 'expensif', and eventually became the modern English word 'expensive' through Middle English.

Initially, it meant 'to weigh out or pay', but over time it evolved into its current meaning of 'costing a lot of money'.