'expression' originates from Latin, specifically the word 'expressio,' where 'ex-' meant 'out' and 'pressare' meant 'to press.'

'expressio' transformed into the Old French word 'expression,' and eventually became the modern English word 'expression' through Middle English.

Initially, it meant 'to press out or convey,' but over time it evolved into its current meaning of 'conveying thoughts or emotions.'