/ Dictionary / Index B bronco: Meaning and Definition of Find definitions for: bron•co Pronunciation: (brong'kō), [key] — pl. -cos. a range pony or mustang of the western U.S., esp. one that is not broken or is imperfectly broken. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: bronco (Thesaurus) bronchus broncobuster Related Content Daily Word Quiz: pundit Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language