There are 18 10-letter words that start with 'ost'.
| osteitides | ostensible | ostensibly |
| ostensoria | osteoblast | osteoclast |
| osteocytes | osteogenic | osteopaths |
| osteopathy | osteosises | osteotomes |
| ostracised | ostracises | ostracisms |
| ostracized | ostracizes | ostracodes |
Note: These 18 10-letter words that start with 'ost' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with oste, ostr, osti, osto, ostl, ostm.
5-letter words start with 'ost' (1)