| Abbreviation | Definition |
|---|---|
| S/R | Stimulus/Response |
| S/S | Samples per Second |
| S/S | Single Sideband |
| S/S | Space Shuttle |
| S/S | Subsystem |
| S/SI | Simulation and System Infrastructure |
| S/Sys | Subsystem |
| S/U | Set Up |
| S/V | Space Vehicle |
| S/V | Supply Valve |
| S/W | Software |
| S1 | Starboard 1 |
| SA | Safing Area |
| SA | Shaft Angle |
| SA | Single Access |
| SA | Site Activation |
| SA | Software Assurance |
| SA | Solar Atmosphere |
| SA | Subaccount |
| SA | Sub-Account |