| Abbreviation | Definition |
|---|---|
| CSOR | Connecticut Southern Railroad |
| CSOX | CITGO Petroleum Corporation |
| CSP | Camas Prairie RailNet |
| CSP | Camas Prairie RailNet Incorporated |
| CSPX | Chesapeake Speciality Products |
| CSPX | Chesapeake Speciality Products (Cities Service) |
| CSR | California State Railroad |
| CSRP | California State Rail Plan |
| CSRR | Conway Scenic Railroad |
| CSRX | Conway Scenic Railroad |
| CSRZ | CSX Transportation |
| CSRZ | CSX Transportation Incorporated |
| CSS | Chicago South Shore and South Bend Railroad |
| CSS | Chicago SouthShore and South Bend Railroad |
| CSTX | Canada Starch Company Incorporated |
| CSTX | Canadian Starch (Casco) |
| CSUU | Container Speditions und Transport, GMBH |
| CSUX | City of Colorado Springs Department of Electric Generation |
| CSVU | Compania Sud Americana de Vapores |
| CSVU | Compania Sud Americana de Vapores GMBH |