'deplate' originates from the prefix 'de-' (from Latin 'de' meaning 'off, away, remove') combined with the noun 'plate' (from Old French 'plate', from Late Latin 'plata' meaning 'a flat metal piece or plate').

'deplate' was formed in modern English by attaching the productive prefix 'de-' to 'plate' in technical contexts (20th century usage), deriving from older words 'plate' (Old French 'plate') and Late Latin 'plata'.

Initially, the base components meant 'plate' (a flat metal piece) and the prefix 'de-' meant removal; over time 'deplate' came to mean specifically 'to remove metal plating or coating', and this specialized meaning has been retained in technical use.