| ort | locality |
| Ortenaukreis | Ortenaukreis |
| Orthanc | Orthanc |
| Orthosie | Orthosie |
| Ortisei | Urtijëi |
| ortnamn | toponym |
| ortodonti | orthodontics |
| ortodox | orthodox |
| Ortodox judendom | Orthodox Judaism |
| Ortodoxa kyrkan | Eastern Orthodox Church |
| Ortodoxa kyrkan av Jerusalem | Greek Orthodox Church of Jerusalem |
| Ortogonala polynom | Orthogonal polynomials |
| ortografi | orthography |
| ortografisk | orthographic |
| Ortomyxovirus | Orthomyxoviridae |
| Ortonormal bas | Orthonormal basis |
| ortoped | orthopedist |
| ortopedi | orthopedics |
| ortopedisk | orthopedic |
| Ortorexi | Orthorexia nervosa |
| Ortostat | Megalithic architectural elements |
| orts- | local |
| ortsbo | local |
| Ortsvektor | Position vector |
| orubblig | determined |
| orubblig kvinna | diehard |
| orubblig man | diehard |
| orubblighet | persistence |
| orubbligt | firmly |
