There are 13 words that start with 'stemm'.
| stemma | stemmy | stemmas | 
| stemmed | stemmer | stemmata | 
| stemmers | stemmery | stemmier | 
| stemming | stemmatic | stemmiest | 
| stemmeries | ||
Note: These 13 words that start with 'stemm' are found from the USA & Canada version of the tournament Scrabble word list.