| Answer | Crossword Clue |
|---|---|
| SINUS | Troublesome bone hollow. |
| FOSSA | Bone hollow |
| FOSSA | Hollow, as in a bone |
| antra | an anatomical cavity within a bone (as the maxilla) or hollow organ (as the stomach) |
| trephine | small circular saw with a center pin mounted on a strong hollow metal shaft to which is attached a transverse handle: used in surgery to remove circular disks of bone from the skull |
| trephined | small circular saw with a center pin mounted on a strong hollow metal shaft to which is attached a transverse handle: used in surgery to remove circular disks of bone from the skull |
