Breadcrumb Home > Dictionary > Index B black disease: Meaning and Definition of Find definitions for: black' disease" Pronunciation: [key] — Vet. Pathol. Vet. Pathol. an acute, usually fatal disease of sheep caused by general intoxication from Clostridium novyi, an anaerobic organism that multiplies in parts of the liver damaged by the common liver fluke. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. black diamond black dog ✖ Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language