| Abbreviation | Definition |
|---|---|
| RI | Rapid Insert |
| RI | Register I |
| RI | Return Index |
| RIR | Resolve Initial References |
| RIRG | Read Inter- Record Gap |
| RJ | Right Justify |
| RL | Register List |
| RLA | Register Linear Address |
| RLCA | Rock Lake Christian Assembly |
| RLP | Refill Light Pen |
| RMB | Reserve Memory Block |
| RMB | Reserve Memory Byte |
| RMD | Rapid Macro Development |
| RME | Register Maintenance And Enquiries |
| RMO | Right Mode Operator |
| RMS | Relocated Module Segment |
| RNA | Rotor Nacelle Assembly |
| RND | Random Number |
| RNE | Return if Not Equal |
| RNF | Residence Not Flag |