There are 13 words that end with 'nitis'.
| adenitis | rhinitis |
| colonitis | laminitis |
| phrenitis | retinitis |
| vaginitis | tendinitis |
| tendonitis | pneumonitis |
| peritonitis | lymphadenitis |
| vulvovaginitis | |
Note: These 13 words that end with 'nitis' are found from the USA & Canada version of the tournament Scrabble word list.