| Abbreviation | Definition |
|---|---|
| RTPB | Real-Time Primary-Backup |
| RTPM | Real Time Power Monitoring |
| RTPU | Real-Time Processing Unit |
| RTU | Remote Transmitter Unit |
| RU | Rack Unit |
| RU | Reduction Unit |
| RUSH | Remote Use of Shared Hardware |
| RVC | Rear Voice Coil |
| RVD | Rainbow Versatile Disc |
| RVD | Remote Virtual Disk |
| RVM | Remote Volume Mirror |
| RVM | Research Virtual Machine |
| RVP | Reverse Voltage Protection |
| RWM | Read-Write Memory |
| RWO | Real World Object |
| RXDO | Receive Disable ,Reception aborted |
| RXE | Remote Expansion Enclosure |
| RXI | Read Expansion Input |
| RXM | Right Expansion Module |
| S | Switch |