| Abbreviation | Definition |
|---|---|
| TREP | Transportation Reimbursement Escort Program |
| TREP | Transportation Research Endowment Program |
| TRF | Transportation Research Forum |
| trf. | transfer |
| TRFM | Transit Ridership Forecasting Model |
| TRG | Transportation Research Group |
| TRI | Transportation Research Institute |
| TRICOM | Transportation Research Implementation Consortium for Operations and Management |
| TRIP | Temporary Registration In Progress |
| TRIP | Transportation Reform And Improvement Plan |
| TRIP | Transportation Reimbursement And Information Program |
| TRIPS | Transportation Intelligent Planning System |
| TRIPS | Transportation Resources For Independent People Of Sandusky |
| TRIS | Traffic and Road Information System |
| TRIS | Transportation Research Information Service |
| TRIS | Transportation Research Information Services |
| TRLU | Transit-Related Land Uses |
| TRNE | Transportation Engineering |
| TRO | Trip Reduction Ordinance |
| TROC | Transportation Resource Oversight Committee |