There are 17 words that start with 'effu'.
| effuse | effulge | 
| effused | effuses | 
| effulged | effulges | 
| effusing | effusion | 
| effusive | effulgent | 
| effulging | effusions | 
| effulgence | effusively | 
| effulgences | effusiveness | 
| effusivenesses | |
Note: These 17 words that start with 'effu' are found from the USA & Canada version of the tournament Scrabble word list.