There are 16 words that start with 'regra'.
| regrade | regraft | regrant | 
| regrate | regraded | regrades | 
| regrafts | regrants | regrated | 
| regrates | regrading | regrafted | 
| regranted | regrating | regrafting | 
| regranting | ||
Note: These 16 words that start with 'regra' are found from the USA & Canada version of the tournament Scrabble word list.