| Abbreviation | Definition |
|---|---|
| MNS | Minneapolis, Northfield and Southern Railway (Canadian Pacific Railway) |
| MNS | Soo Line Railroad Company |
| MNSR | Minnesota Southern Railway |
| MNTX | Minnesota Transportation Museum |
| MNWX | Minnesota Department of Public Service Weights and Measures Division |
| MOBX | Mobil Oil Corporation |
| MOBX | Mobil Oil Corporation (Exxon-Mobil Corporation) |
| MOC | Missouri Central Railroad |
| MOCX | Missouri Portland Cement |
| MOD | Missouri Pacific Railroad |
| MOD | Modesto Amtrak Station |
| MOEX | Morgan Engineering |
| MOFX | Maxton Oil and Fertilizer |
| MOFX | Maxton Oil and Fertilizer Company |
| MOGX | C. W. Brooks Incorporated |
| MOGX | Mangum Oil & Gas (C.W. Brooks) |
| MOHX | Monsanto |
| MOHX | Solutia Incorporated |
| MOLU | Mitsui O. S. K. Lines Limited |
| MOLU | Mitsui O.S.K. Lines |