/ Dictionary / Index R rustproof: Meaning and Definition of Find definitions for: rust•proof Pronunciation: (rust'prf"), [key] — adj. not subject to rusting. —v.t. to coat with a substance that prevents rusting. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: rustproof (Thesaurus) rustout rustproofing Related Content Daily Word Quiz: placid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language