| Abbreviation | Designation | |
|---|---|---|
| 91 | Zugtelefonnummer vom Zugchef (German) | rail transport operations |
| TKAB | Tågkompaniet (Swedish) Swedish Train Company | railway company |
| 91 | Elektrolokomotiven (ab 100 km/h) (German) Electric locomotive | class |
| 91 / TN | Tunisia, Tunisian Republic | country code |
| 91 / NSTN | Steinach (b Rothenburg ob der Tauber) (German) | station code |