/ Dictionary / Index B bact.: Meaning and Definition of Find definitions for: bact. Pronunciation: [key] bacterial. bacteriology. bacterium. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Bacon's Rebellion -bacter Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language