'deposit' originates from Latin, specifically the word 'depositum' (past participle of 'deponere'), where 'de-' meant 'down' and 'ponere' meant 'to place or put.'

'deposit' passed into Old French as 'deposer' and then into Middle English (e.g., 'depositen'/'deposited'), eventually becoming the modern English word 'deposit.'

Initially, it meant 'to put down or place' (physically), but over time it expanded to include 'to put for safekeeping' (especially money) and the idea of 'material left by natural processes' (sediment).