| Abbreviation | Definition |
|---|---|
| GSO | Ground Safety Office |
| GSO | Ground Support Operations |
| GSO | GSFC (Goddard Space Flight Center) Security Office |
| GSO | Gyroscope Storage Oven |
| GSOC | Guide Star Occultation Utility |
| GSP | Global Service Providing |
| GSRP | Ground Safety Review Panel |
| GSS | Ground Support Software |
| GSS | Ground Support System |
| GSSA | Ground Support Systems Activation |
| GSSC | Ground Support Simulation Computer |
| GSSC | Ground Support Systems Contractor |
| GSSI | Ground Support System Integration |
| GST | Ground System Test |
| GSTAR | GTE Spacenet Satellite |
| GSTDN | Ground Satellite Tracking Data Network |
| GSTDN | Ground Space Flight Tracking and Data Network |
| GSTF | Ground Systems Test Flow |
| GSU | Gas Servicer Unit |
| GSVP | Ground Support Verification Plan |