| Abbreviation | Definition |
|---|---|
| NGOU | Scoa Incorporated |
| NGTX | Suburban Propane - Division of Quantum Chemical |
| NGTX | Vangas (Suburban Propane) |
| NH | Consolidated Rail Corporation |
| NH | New York, New Haven and Hartford Railroad (CSX Transportation) |
| NHCR | New Hampshire Central Railroad |
| NHN | New Hampshire Northcoast Corporation |
| NHR | Namtrac Heavy Rail |
| NHRR | New Hope and Ivyland Rail Road |
| NHRR | New Hope and Ivyland Railroad |
| NHRY | New Haven Rail Yard |
| NHUU | Hub Group Incorporated |
| NHUU | Hub Group, Inc. |
| NHVT | New Hampshire and Vermont Railroad |
| NHVT | New Hampshire and Vermont Railroad Company |
| NHVX | East Carolina Chapter National Railway Historical Society |
| NIAJ | Niagara Junction Railway (Conrail) |
| NIAX | Niagara and Western New York Railroad |
| NICD | Northern-Indiana Commuter Transportation District |
| NICD | South Shore Line (NICTD) |