| Abbreviation | Designation | |
|---|---|---|
| Ol | Oberlausitz (German) Upper Lusatia | |
| OL | Oberleitung (German) | railway installation |
| OL | Oldenburg (Oldb) Hbf, Stadt Oldenburg (German) | fare point / vehicle registration plate |
| Ol | Oleby (Swedish) | station code |
| Öl | Ölme (Swedish) | station code |