| Abbreviation | Definition |
|---|---|
| AMAX | AMAX Coal |
| AMAX | AMAX Coal Company |
| AMBU | Amber Line |
| AMBU | Amber Line Incorporated |
| AMBX | American Boiler Works Incorporated |
| AMBX | Amherst Industries (American Boiler Works) |
| AMC | Amador Central Railroad |
| AMC | Arkansas Louisiana and Mississippi Railroad Company |
| AMC | Arkansas, Louisiana and Mississippi Railroad |
| AMCX | Amoco Chemical Company |
| AMCX | Amoco Chemicals Corporation (BP Amoco Chemical) |
| AMCZ | AMC Chemical (Interbulk) |
| AMCZ | Interbulk Incorporated |
| AMEX | Albamex (Allied Entreprises) |
| AMFU | Amphibious Container Leasing |
| AMGX | AMG Resources Corporation |
| AMHR | Amherst Industries (Landisville Railroad) |
| AMHR | Landisville Railroad Incorporated |
| AMIU | American Marine Industries |
| AMIU | American Marine Industry |