/ Dictionary / Index P Pierce's disease: Meaning and Definition of Find definitions for: Pierce''s disease" Pronunciation: [key] — Plant Pathol. Plant Pathol. a disease of grapes caused by a rickettsialike organism, characterized by dwarfing of vines, mottling of woody tissues, and plant death. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. pierced piercing Related Content Daily Word Quiz: cygnet Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language