| Abbreviation | Definition |
|---|---|
| SR | Source Register |
| SR | Subtract Register |
| SRA | Shop Repairable Assembly |
| SRL | Shift Register Latch |
| SRL | Shift Right Logical |
| SRL | Short Repeats Left |
| SSB | Scramble Status Byte |
| SSC | Slot Size Code |
| SSD | Store Stack Double-word |
| SSJ | Select Stacker and Jam |
| SSLA | Solid State Lighting Assembly |
| SSM | Source Support Module |
| SSP | Set Stack Pointer |
| SSP | System Stack Pointer |
| ST | Show Turtle |
| STC | Set Carry Flag |
| STD | Set Direction Flag |
| STHA | Skin Temperature Heater Assembly |
| STI | Set Interrupt Enable Flag |
| STK | Stack |