There are 18 words that end with 'ffiest'.
| iffiest | buffiest | daffiest |
| huffiest | miffiest | puffiest |
| chaffiest | chuffiest | cliffiest |
| draffiest | gruffiest | fluffiest |
| sniffiest | snuffiest | spiffiest |
| stuffiest | scruffiest | squiffiest |
Note: These 18 words that end with 'ffiest' are found from the USA & Canada version of the tournament Scrabble word list.