| Abbreviation | Definition |
|---|---|
| GGS | Global Geospace Science |
| GH2 | Gaseous Hydrogen |
| GHA | General Housekeeping Area |
| GHA | Greenwich Hour Angle |
| GHC | Ground Half Coupling |
| GHe | Gaseous Helium |
| GHX | Ground Heat Exchanger |
| GHz | Gigahertz |
| GIA | GPC (General Purpose computer) Interface Adapter |
| GIANT | Goddard Image Analysis and Navigation Tool |
| GICB | Ground Initiated Communications, channel B |
| GIDEP | Government-Industry Data Exchange Program |
| GIE | Ground Instrumentation Equipment |
| GIF | Geospatial Innovation Facility |
| G-II | Gulfstream II (Shuttle Training Aircraft) |
| GIID | General Instrument Interface Document |
| GIM | Generalized Information Management |
| GIMP | Gnu Image Manipulation Project |
| GIRD | Ground Integration Requirements Document |
| GIS | Geography In Space |