| Abbreviation | Definition |
|---|---|
| GRNS | Gamma-Ray and Neutron Spectrometer |
| GRS | Gamma Ray Spectrometer |
| GS | Gamma Stable |
| Gs | Gauss |
| GS | Glazed Surfaces |
| GS | Gramse Spectrum |
| GSL | Generalized Second Law |
| GSO | Geostationary Orbit |
| GSP | Generalized Sequential Pattern |
| GSQM | General Superfield Quantization Method |
| GTR | Generalized Threshold Replenishment |
| GTRD | Generalized Transverse Resonance Diffraction |
| GUE | Gaussian Unitary Ensemble |
| GURFRIP | Global Utility Restructure For Relative Intelligent Process |
| GUT | Grand Unification Theory |
| GWC | Generalized Wave Continuity |
| GWCE | Generalized Wave Continuity Equation |
| GWR | Guided Wave Radar |
| GWRI | Gravitonic Wave Resonance Imaging |
| GXR | Grazing X-ray Reflectometry |