| Abbreviation | Definition |
|---|---|
| CNL | Columbia, Newberry and Laurens Railroad (CSX Transportation) |
| CNLX | CANAC International |
| CNLX | CANAC International Incorporated |
| CNMZ | Conrail Mercury (Norfolk Southern) |
| CNMZ | Consolidated Rail Corporation |
| CNNU | Compania Nacional de Nabegacao |
| CNoAR | Canadian Northern Alberta Railway |
| CNOC | Consolidated National Operations Center |
| CNoPR | Canadian Northern Pacific Railway |
| CNOR | Canadian Northern Ontario Railway |
| CNoR | Canadian Northern Railway |
| CNOR | Cincinnati Northern |
| CNOW | Columbia and Northern Railway |
| CNOW | Columbia and Northern Railway Company |
| CNOX | Canadian Oil Co. (Shell Canada) |
| CNPR | Canadian Northern Pacific Railway |
| CNPU | Canadian National Railway |
| CNPZ | Canadian National Railway |
| CNQ | Canadian National Railway |
| CNR | Canadian National Railway Company |