| Osteostraci | Osteostraci |
| Osterberg | Osterberg |
| Osterbruch | Osterbruch |
| Osterburg | Osterburg |
| Osterburken | Osterburken |
| Osterby | Osterby |
| Ostercappeln | Ostercappeln |
| Ostereistedt | Ostereistedt |
| Osterfeld | Osterfeld |
| Osterhofen | Osterhofen |
| Osterholz | Osterholz |
| Osterholz-Scharmbeck | Osterholz-Scharmbeck |
| Osterley tube station | Osterley |
| Ostermundigen | Ostermundigen |
| Ostern | Ostern |
| Osternienburg | Osternienburg |
| Osterode | Osterode am Harz |
| Osterode am Harz | Osterode am Harz |
| Osterrade | Osterrade |
| Osterrönfeld | Osterrönfeld |
| Osterwald | Osterwald |
| Osterwieck | Osterwieck |
| Osterzell | Osterzell |
| Osterøy | Osterøy |
| Ostfildern | Ostfildern |
| Ostheim | Ostheim vor der Rhön |
| Osthofen | Osthofen |
| Ostholstein | Oost-Holstein |
| Ostia | Ostia Antica |
| Ostia Antica | Ostia Antica |
| Ostiglia | Ostiglia |
| Ostlegionen | Ostlegion |
| ostler | stalknecht |
| Ostmark | Ostmark |
| Ostpolitik | Ostpolitik |
| Ostprignitz-Ruppin | Ostprignitz-Ruppin |
| Ostrach | Ostrach |
| ostracize | uitsluiten |
| Ostrava | Ostrava |
| Ostrava-City District | Okres Ostrava-město |
| Ostravice | Ostravice |
| Ostravice River | Ostravice |
| Ostrhauderfehn | Ostrhauderfehn |
| ostrich | struisvogel |
| ostrich policy | struisvogelpolitiek |
| Ostritz | Ostritz |
| Ostrobothnia | Österbotten |
| Ostrog monastery | Ostrog |
| Ostrogoth | Oostgoot |
| Ostrogoths | Ostrogoten |
| Ostroh | Ostrog |
| Ostrohe | Ostrohe |
| Ostroróg | Ostroróg |
| Ostrov | Ostrov |
| Ostrowiec County | Powiat Ostrowiecki |
| Ostrowiec Świętokrzyski | Ostrowiec Świętokrzyski |
| Ostrołęka | Ostrołęka |
| Ostrołęka County | Powiat Ostrołęcki |
| Ostrya | Hopbeuk |
| Ostrzeszów | Ostrzeszów |
| Ostrzeszów County | Powiat Ostrzeszowski |
| Ostróda | Ostróda |
| Ostróda County | Powiat Ostródzki |
| Ostrów Lubelski | Ostrów Lubelski |
| Ostrów Mazowiecka | Ostrów Mazowiecka |
| Ostrów Mazowiecka County | Powiat Ostrowski |
| Ostrów Wielkopolski | Ostrów Wielkopolski |
| Ostrów Wielkopolski County | Powiat Ostrowski |
| Oststeinbek | Oststeinbek |
| Ostvorpommern | Ostvorpommern |
| Ostwald process | Ostwaldproces |
| Ostwind | Ostwind |
| Osu Castle | Christiansborg |
| Osuga River | Osoega |
| Osun State | Osun |
| Osun-Osogbo | Osun-Osogbo |
| Osvaldo Ardiles | Osvaldo Ardiles |
| Osvaldo Cavandoli | Osvaldo Cavandoli |
| Osvaldo Dorticós Torrado | Osvaldo Dorticós Torrado |
| Osvaldo Pugliese | Osvaldo Pugliese |
| Oswald Achenbach | Oswald Achenbach |
| Oswald Mosley | Oswald Mosley |
| Oswald of Northumbria | Oswald van Northumbria |
| Oswald Spengler | Oswald Spengler |
| Oswaldo Piazza | Oswaldo Piazza |
| Oswego | Oswego |
| Oswiecim | Oswiecim |
| Oswiu of Northumbria | Oswiu van Northumbria |
| OTA | OTA |
| Otaci | Otaci |
| Otago | Otago |
| Otaheite gooseberry | Grosella |
| Otakar II of Bohemia | Ottokar II van Bohemen |
| otalgia | oorpijn |
| Otava River | Otava |
| OTC Doors-Lauretana | OTC Doors - Lauretana |
| Otelfingen | Otelfingen |
| Otello | Otello |
| OTEP | Otep |
| Otepää | Otepää |
| Otepää Commune | Otepää |
| Otero County | Otero County |
| Otfried Preußler | Otfried Preußler |
