There are 11 words that start with 'prosa'.
| prosaic | prosaism | prosaist |
| prosaical | prosaisms | prosaists |
| prosateur | prosateurs | prosaically |
| prosauropod | prosauropods | |
Note: These 11 words that start with 'prosa' are found from the USA & Canada version of the tournament Scrabble word list.