There are 17 words that start with 'serial'.
| serial | serials | 
| serially | serialise | 
| serialism | serialist | 
| serialize | serialised | 
| serialises | serialisms | 
| serialists | serialized | 
| serializes | serialising | 
| serializing | serialization | 
| serializations | |
Note: These 17 words that start with 'serial' are found from the USA & Canada version of the tournament Scrabble word list.