/ Dictionary / Index B biostrome: Meaning and Definition of Find definitions for: bi•o•strome Pronunciation: (bī'u-strōm"), [key] — n. Geol. a bedded, blanketlike sedimentary deposit of organic origin built by marine organisms and including shell beds, flat reefs, and corals. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. biostratigraphy biosynthesis Related Content Daily Word Quiz: fabricate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language