/ Dictionary / Index B branchio-: Meaning and Definition of Find definitions for: branchio- Pronunciation: [key] a combining form meaning “gills,” used in the formation of compound words: branchiopod. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. branchiform branchiopneustic Related Content Daily Word Quiz: sinister Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language