| Abbreviation | Definition |
|---|---|
| TRIN | Trinidad Railway Incorporated |
| TRIU | Triton Container International |
| TRIU | Triton Container International Incorporated |
| TRIX | MidAmerican Energy Company |
| TRIX | Midwest Energy Services |
| TRLU | TAL International |
| TRLU | Transamerica Leasing Incorporated |
| TRLX | Texas Railcar Leasing |
| TRLX | Texas Railcar Leasing Company |
| TRMW | Tacoma Rail Mountain Division |
| TRMX | The Railroad Museum-TRM Industries |
| TRMX | TRM Industries |
| TRNX | General Electric Railcar Services Corporation |
| TRNX | Trinity Railcar Leasing Corporation |
| TROU | Trans Ocean Limited |
| TRPU | Tropical Trailer Leasing |
| TRPX | AmeriGas Propane L. P. |
| TRPX | Tropigas of Florida |
| TRRA | Terminal Railroad Association of St Louis |
| TRRA | Terminal Railroad Association of St. Louis |