There are 12 words that start with 'osteop'.
| osteopath | osteopaths | 
| osteopathy | osteopathic | 
| osteoplasty | osteopathies | 
| osteoplastic | osteoporoses | 
| osteoporosis | osteoporotic | 
| osteoplasties | osteopathically | 
Note: These 12 words that start with 'osteop' are found from the USA & Canada version of the tournament Scrabble word list.