| Abbreviation | Definition |
|---|---|
| SIS | Scanning Imaging Spectrometer |
| SIS | Serial Input Special |
| SIS | Shuttle Information System |
| SIS | Shuttle Interface Simulator |
| SIS | Simulator Interface System |
| SIS | Software Implementation Specification |
| SIS | Software Integrated Schedule |
| SIS | Standard Interface Specification |
| SIS | Superconducting-Insulating-Superconducting |
| SIS | Systems Integration Schedule |
| SISS | Scientific Instrument Support Structure |
| SISWG | STS Integrated Schedule Working Group |
| SIT | Seal Initiation Temperature |
| SIT | Shuttle Integrated Test |
| SIT | Shuttle Interface Test |
| SIT | SITuation |
| SIT | Software Integration Test |
| SIT | SSV (Space Shuttle Vehicle) Integrated Test |
| SIT | System Implementation Team |
| SITA | Societe Internationale de Telecommunications Aeronautiques |