There are 17 words that start with 'ferre'.
| ferrel | ferret | ferrels | 
| ferrets | ferrety | ferreled | 
| ferreous | ferreted | ferreter | 
| ferreling | ferrelled | ferreters | 
| ferreting | ferredoxin | ferrelling | 
| ferretings | ferredoxins | |
Note: These 17 words that start with 'ferre' are found from the USA & Canada version of the tournament Scrabble word list.