/ Dictionary / Index R rainproof: Meaning and Definition of Find definitions for: rain•proof Pronunciation: (rān'prf"), [key] — adj. impervious to rain; keeping out or unaffected by rain: a rainproof cover; a rainproof coat. —v.t. to make rainproof. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: rainproof (Thesaurus) rainout rain shadow Related Content Daily Word Quiz: maritime Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language