There are 16 8-letter words that start with 'ost'.
| osteitic | osteitis | osteoids | osteomas |
| osteoses | osteosis | ostinati | ostinato |
| ostiolar | ostioles | ostmarks | ostomate |
| ostomies | ostracod | ostracon | ostrakon |
Note: These 16 8-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)