| offenkundig | apparent |
| offenkettig | open-chain |
| offenherzig | frank candid open revealing |
| Öffnung | opening |
| Affenkäfig | monkey cage |
| unkundig | unknowledgeable |
| fachkundig | adept |
| ortskundig | locally knowledgeable with local knowledge |
| Offenheit | candor |
| Offenlegung | disclosure |
| Hoffnung | hope |
| Kofferkuli | baggage cart |
| Offenbarung | revelation Apocalypse Revelation Revelations |
| offensiv | offensive |
| Effendi | effendi |
| Pfennig | pfennig |
| Absenkung | dip |
| Algenkunde | algology |
| Ansenkung | countersink |
| Höhlenkunde | speleology |