There are 18 words that start with 'worth'.
| worth | worths | 
| worthy | worthed | 
| worthful | worthier | 
| worthies | worthily | 
| worthing | worthiest | 
| worthless | worthiness | 
| worthwhile | worthlessly | 
| worthinesses | worthlessness | 
| worthwhileness | worthlessnesses | 
Note: These 18 words that start with 'worth' are found from the USA & Canada version of the tournament Scrabble word list.