'decrease' originates from Old French, specifically the word 'decreistre,' where 'de-' meant 'down' and 'crescere' meant 'to grow.'

'decreistre' transformed into the Middle English word 'decrecen,' and eventually became the modern English word 'decrease.'

Initially, it meant 'to grow less,' but over time it evolved into its current meaning of 'to become smaller or less in size, amount, or degree.'