| Abbreviation | Definition |
|---|---|
| AWCX | Airco Welding Products |
| AWDX | Atlantic of New York |
| AWDX | Atlantic of New York Incorporated |
| AWIX | Albright and Wilson Americas |
| AWIX | Albright and Wilson Americas Incorporated |
| AWP | Atlanta and West Point Railroad (CSX Transportation) |
| AWP | CSX Transportation Incorporated |
| AWRR | Austin Western Railroad |
| AWVX | 20th Century Fox |
| AWW | Algers Winslow and Western Railway |
| AWW | Algers, Winslow and Western Railway |
| AWXU | Alaska West Express |
| AWXX | East Carbon Development |
| AWZZ | Ahnapee & Western (McCloud Railway) |
| AWZZ | McCloud Railway Company |
| AXCU | Ace Transportation |
| AXCU | Ace Transportation Company Incorporated |
| AXXZ | Agricultural Express of America |
| AYSS | Allegheny and South Side Railway |
| AZCR | Arizona Central Railroad |