There are 14 words that start with 'discus'.
| discus | discuss | discuses | 
| discussed | discusser | discusses | 
| discussant | discussers | discussing | 
| discussion | discussable | discussants | 
| discussible | discussions | |
Note: These 14 words that start with 'discus' are found from the USA & Canada version of the tournament Scrabble word list.