| Osteopenie | osteopenia |
| Osteogenese | osteogenesis |
| Osteologie | osteology |
| Ontogenie | ontogeny |
| Ostende | Ostend |
| Osteologin | osteologist |
| Osteologe | osteologist |
| Osteoporose | osteoporosis |
| Osterei | Easter egg |
| Osterferien | Easter holidays |
| Osterkerze | Paschal candle |
| Osterzeit | Easter |
| Östrogen | estrogen oestrogen œstrogen |
| Stephanie | Stephanie |
| Stefanie | Fanny Stephanie |
| Neopenis | neopenis |
| Neotenie | neoteny |
| Asthenie | asthenia |
| Teenie | teen |
| Ostermond | April |