| 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 |
| Othello | Othello |
| other | ander |
| other people's | andermans |
| other side | overkant |
| other than | afgezien van |
| Other Voices | Other Voices |
| others | andere |
| otherwise | in het andere geval |
| otherworldly | wereldvreemd |
| Othmarsingen | Othmarsingen |
| Othniel Ben Kenaz | Otniël |
| Othniel Charles Marsh | Othniel Charles Marsh |
| Otho | Otho |
| Otis Redding | Otis Redding |
| Otl Aicher | Otl Aicher |
| Otmar Hasler | Otmar Hasler |
| Otmuchów | Otmuchów |
