There are 332 10-letter words that start with 'pre'.
Note: These 332 10-letter words that start with 'pre' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with pres, prec, prep, pred, prea, pref, prem, pret, pree, prev, prel, preb, prer, preo, preh, prew, pren, prei, preg, prej, preu, preq, prey, prex, prez, prek.
4-letter words start with 'pre' (5)