There are 20 11-letter words that start with 'prep'.
Note: These 20 11-letter words that start with 'prep' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with prepa, prepo, prepr, prepu, prepl, prepp, prepe, preps, prepi.
5-letter words start with 'prep' (1)