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v. Present participle of rustproof.

"Other displays focus on how Toyota's car technologies have been applied to houses, including a rustproofing process that preserves the house's steel structure for decades; a device to quiet engines that can help damp vibrations from foot traffic on the upper floors; and a single key that can be coded to open both the owner's Toyota car and Toyota home."

goofing    proofing    roofing    spoofing