There are 16 9-letter words that start with 'ef'.
| effecters | effecting | effective |
| effectors | effectual | efferents |
| efficient | effluence | effluents |
| effluvial | effluvium | effluxion |
| effortful | effulgent | effulging |
| effusions | ||
Note: These 16 9-letter words that start with 'ef' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with eff, eft, efs.
3-letter words start with 'ef' (3)