/ Dictionary / Index B brei: Meaning and Definition of Find definitions for: brei Pronunciation: (brī), [key] — n. Microbiology. a suspension of finely divided tissue in an isotonic medium, used chiefly as a culture for certain viruses. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. bregma Breidha Fjord Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language