rustproofPronunciation: /ˈrʌs(t)pruːf/Translate rustproof | into German | into Italian | into Spanish Definition of rustproof adjective (of metal or a metal object) not susceptible to corrosion by rust: rustproof screws verb [with object] make resistant to corrosion by rust: was it practicable to rustproof metallic structures, as one did cars?rustproof in other Oxford dictionaries Definition of rustproof in the US English dictionary