| Abbreviation | Definition |
|---|---|
| DGNO | Dallas, Garland and Northeastern Railroad |
| DGVR | Durbin and Greenbrier Valley Railroad |
| DH | Delaware and Hudson Railway |
| DH | Delaware and Hudson Railway Company Incorporated |
| DHEU | D&H Equipment |
| DHNY | Delaware and Hudson Railway |
| DHNY | Delaware and Hudson Railway Company Incorporated |
| DHPX | Degussa Corporation |
| DHPX | Dugassa Corporation |
| DHRU | Den Hartogh NV |
| DICX | Pure Carbonic |
| DIIU | Dart Intermodal |
| DIIU | Dart Intermodal Incorporated |
| DIRFT | Daventry International Rail Freight Terminal |
| DIRN | Defined Interstate Rail Network |
| DJBX | Donald j. Bertel - Gandy Dancer Incorporated |
| DJBX | Donald J. Bertel dba Gandy Dancer Inc. |
| DJJX | David J. Joseph Company |
| DJJX | David J. Joseph Transportation |
| DJLX | David J. Joseph Leasing |