| Abbreviation | Definition |
|---|---|
| PICK | Pickens Railroad |
| PICK | Pickens Railway Company |
| PICOP | Persons in Charge of Possession |
| PICU | Pickfords Removals Limited |
| PIFX | Pifer Tank Car |
| PIFX | Pifer Tank Car Company |
| PIGZ | Tranfax - Division of Fresh Intermodal Transport Incorporated |
| PIGZ | Tranfax-Division of Fresh Intermodal Transport |
| PIR | Pittsburgh Industrial Railroad |
| PIR | Pittsburgh Industrial Railroad Incorporated |
| PIVX | Pivotal Enterprises Corporation |
| PJR | Port Jersey |
| PJR | Port Jersey Railroad |
| PJRL | Penn Jersey Rail Lines |
| PJRL | Penn Jersey Rail Lines Incorporated |
| PKHP | Pickens Railway Co-Honea Path Division |
| PKHP | Pickens Railway Company - Honea Path Division |
| PKO | Power Knock Out |
| PKSX | Peter Kiewit Sons |
| PLCX | General Electric Railcar Services Corporation |