There are 3 15-letter words that start with 'ben'.
| benightednesses | benzanthracenes | 
| benzodiazepines | |
Note: These 3 15-letter words that start with 'ben' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with bene, benz, bend, bent, benc, beni, benn, bena, benu, beng, benj, beno, bens.
4-letter words start with 'ben' (4)