| Abbreviation | Definition |
|---|---|
| TTTZ | Puerto Rican Maritime Authority |
| TTUX | Trailer Train (TTX Corporation) |
| TTUX | TTX Company |
| TTVX | Trailer Train (TTX Corporation) |
| TTVX | TTX Company |
| TTWU | Canadian National Railway |
| TTWX | Trailer Train (TTX Corporation) |
| TTWX | TTX Company |
| TTWZ | Canadian National Railway |
| TTX | Trailer Train (TTX Corporation) |
| TTX | Trailer Train Corporation |
| TTX | TTX Company |
| TTZX | Trailer Train (TTX Corporation) |
| TTZX | TTX Company |
| TUGX | Texas Utilities Generating |
| TUGX | Texas Utilities Mining Company |
| TULU | Container Solutions |
| TUPX | Texas Ultra Pure |
| TURO | Tabriz Urban Railway Organisation |
| TURO | Tabriz Urban Railway Organization |