| Term | Definition | Contributor | Modified |
|---|---|---|---|
| Railroads, Monorail | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads, Mountain | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads, Narrow-gage | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Operation | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Parly works to 1850 | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Passenger-cars | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Passenger-ears | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Passenger traffic | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Passes | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Pensions | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Pro-rating tables | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads, Rack | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Rafes | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Rails | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Rails--Fastenings | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Rates | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Record and correspondence files | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Refrigerator-cars | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Repair-shops | No definition provided | Christopher Rauch | 2023.12.01 |
| Railroads--Rolling-stock | No definition provided | Christopher Rauch | 2023.12.01 |