There are 8 14-letter words that start with 'bro'.
| bromocriptines | bronchiectases | 
| bronchiectasis | bronchodilator | 
| bronchoscopies | bronchoscopist | 
| bronchospastic | brontosauruses | 
Note: These 8 14-letter words that start with 'bro' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with broa, broo, brow, bron, brom, broc, brok, broi, brot, brog, brou, bros, brol.
4-letter words start with 'bro' (3)