There are 13 words that end with 'cosis'.
| mycosis | sycosis |
| narcosis | silicosis |
| toxicosis | varicosis |
| psittacosis | actinomycosis |
| blastomycosis | cysticercosis |
| cryptococcosis | echinococcosis |
| thyrotoxicosis | |
Note: These 13 words that end with 'cosis' are found from the USA & Canada version of the tournament Scrabble word list.