/ Dictionary / Index C crown rust: Meaning and Definition of Find definitions for: crown' rust" Pronunciation: [key] — Plant Pathol. Plant Pathol. a disease of oats and other grasses, characterized by the formation, on the leaves, of orange or black spores, caused by a rust fungus, Puccinia coronata. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. crown rot crown saw Related Content Daily Word Quiz: rustic Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language