There are 11 words that start with 'mulli'.
| mulling | mullion | 
| mullite | mulligan | 
| mullions | mullites | 
| mulligans | mullioned | 
| mullioning | mulligatawny | 
| mulligatawnies | |
Note: These 11 words that start with 'mulli' are found from the USA & Canada version of the tournament Scrabble word list.