Abbreviations were often used to make communication more efficient in the
days of Morse code. Here are some that are fairly common.
| 19D | "19 Order" Displayed |
| 24-RL | A locomotive brake system |
| ABS | Automatic Block Signal System |
| ACS | Automatic Cab Signal System |
| ACT | Against Current of Traffic |
| App ckt | Approach Circuit |
| ATC | Automatic Train Control |
| ATS | Automatic Train Stop |
| C&E | Conductor and Engineer |
| CCOR | Consolidated Code of Operating Rules |
| Ckt | Circuit |
| Com | Complete |
| Condr | Conductor |
| CTC | Centralized Traffic Control System |
| Cy | Copy |
| Dbl trk | Double Track |
| Dispr | Train Dispatcher |
| Div | Division |
| Divn | Division |
| DT | Double Track |
| Eng | Engine |
| Engr | Engineer |
| Frt | Freight |
| Hwy | Highway |
| Jct | Junction |
| MBS | Manual Block System |
| Mins | Minutes |
| MP | Mile Post |
| MPH | Miles Per Hour |
| MT | Main Track |
| ND | Not Displayed |
| No | Number |
| OK | Correct |
| Opr | Operator |
| Orig | Originating |
| OS | Train Report |
| OT | On Time |
| OTS | Out of Service |
| PK | Inspection |
| Psgr | Passenger |
| SD | "Stop" Displayed |
| Str | Streamline |
| Subdivn | Subdivision |
| Supt | Superintendent |
| Swtg | Switching |
| T&E | Train and Engine |
| Trk | Track |
| Trk ckt | Track Circuit |
| TTTO | Timetable and Train Order |
| UCOR | Uniform Code of Operating Rules |
| X | Train will be held until train order is made complete |
| YM | Yardmaster |
