There are 18 words that start with 'horri'.
| horrid | horrify |
| horrible | horribly |
| horrider | horridly |
| horrific | horribles |
| horridest | horrified |
| horrifies | horridness |
| horrifying | horribleness |
| horridnesses | horrifically |
| horrifyingly | horriblenesses |
Note: These 18 words that start with 'horri' are found from the USA & Canada version of the tournament Scrabble word list.