There are 15 words that start with 'spiro'.
| spiroid | spirogyra |
| spirochete | spirogyras |
| spirometer | spirometry |
| spirochaete | spirochetal |
| spirochetes | spirometers |
| spirometric | spirochaetes |
| spirometries | spirochetoses |
| spirochetosis | |
Note: These 15 words that start with 'spiro' are found from the USA & Canada version of the tournament Scrabble word list.