| Abbreviation | Definition |
|---|---|
| THSR | Taiwan High Speed Rail |
| THSX | New York, Susquehanna, & Western Technical and Historical Society |
| TI | Turners Island |
| TIBR | TimberRock Railroad |
| TIBR | TimberRock Railroad Company Incorporated |
| TIF | Transport Innovation Fund |
| TIJ | Trafikbolaget Ingalunda Jernväg |
| TILU | Tirrenia Di Navigazione S.P.A. |
| TILU | Tirrenia di Navigazione, SP. A. |
| TILX | Trinity Industries Leasing |
| TILX | Trinity Industries Leasing Company |
| TIMX | Trinity Industries Leasing |
| TIMX | Trinity Industries Leasing Company |
| TINU | Tioxide |
| TINU | Tioxide ( U. K.) Limited |
| TINX | Trinity Industries Leasing |
| TIPP | Tippecanoe Railway |
| TIPZ | TIP Intermodal Services |
| TIPZ | Transport International Pool Incorporated |
| TIRL | Tonawanda Island Railroad |