| Abbreviation | Definition |
|---|---|
| GPTE | General Purpose Test Equipment |
| GPU | Ground Power Unit |
| GPUR | GOAL (Ground Operations Aerospace Language) Test Procedure Update Request |
| GR | Ground Rule |
| GRACE | Gravity Recovery and Climate Experiment |
| GRACE | Gravity Research And Climate Experiment |
| GRAIL | Gravitational Radiation Antenna In Leiden |
| GRAIL | Gravity Recovery and Interior Laboratory |
| GRB | Gamma Ray Burst |
| GRB | Gamma Ray Bursts |
| GRC | Glenn Research Center |
| GRE | Gamma Ray Explorer |
| GRID | Graphic Retrieval and Information Display |
| GRIN | Great Resources In Nasa |
| GRIP | Gamma Ray Imaging Payload |
| GRIP | Genesis and Rapid Intensification Processes (hurricane research) |
| GRN | GReeN |
| GRO | Gamma Ray Observatory |
| GRS | Galaxy Rocket System |
| GRS | Gravitational Reference Sensor |