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definitions

rustproofing

[ruhst-proo-fing]

noun

the process of making metal rustproof.
Also called rust·proof·er. a substance used in this process.

Origin of rustproofing

First recorded in 1915–20; rustproof + -ing1

rustproof

[ruhst-proof]

adjective

not subject to rusting.

verb (used with object)

to coat with a substance that prevents rusting.

Origin of rustproof

First recorded in 1685–95; rust + -proof
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for rustproofing

rustproof

adjective

treated against rusting
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012