/ Dictionary / Index B biohazard: Meaning and Definition of Find definitions for: bi•o•haz•ard Pronunciation: (bī'ō-haz"urd), [key] — n. a pathogen, esp. one used in or produced by biological research. the health risk posed by the possible release of such a pathogen into the environment. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: biohazard (Thesaurus) biography bioherm Related Content Daily Word Quiz: cetacean Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language