/ Dictionary / Index B boro-: Meaning and Definition of Find definitions for: boro- Pronunciation: [key] a combining form used in the names of chemical compounds in which boron is present: borofluoride. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. bornyl formate Borodin 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