| Acronym | Meaning |
| GFN | Grain Fineness Number |
| GFP | Green Fluorescent Protein |
| GFPE | Generalized Fokker-Planck Equation |
| GFQMC | Green Function Quantum Monte Carlo |
| GFR | Glomerular Filtration Rate |
| GFRC | Glass Fiber Reinforced Cement |
| GFRP | Glass Fiber Reinforced Plastics |
| GGA | Generalized Gradient Approxn. |
| GGC | Generalized Gradient-corrected (density-functional) |
| GGG | Gallium Gadolinium Garnet |
| GGS | Global Geospace Science |
| GGWD | Generalized Gaussian Wave-packet |
| GGWPD | Generalized Gaussian Wave-packet Dynamics |
| GH | Growth Hormone |
| GHCN | Global Historical Climatology Network |
| GHD | Growth Hormone Deficiency |
| GHF | Generalized Hartree-Fock Method |
| GHF | Generalized Hellmann-Feynman (theorem) |
| GHG | Greenhouse Gases |
| GHL | Generalized Heitler-London |
| GHO | Generalized Hybrid Orbital (ao) |
| GHR | Growth Hormone Receptor |
| GHRF | Growth Hormone-releasing Factor |
| GHRH | Growth Hormone-releasing Hormone |
| GHRS | Goddard High Resolution Spectrograph |
| GHSV | Gas Hourly Space Velocity |
| GI | Many Electron Wave Functions That Are Simultaneously Eigen-functions Of The Total Spin Projection Operators And Satisfy The Pa |
| GIABS | Gastro-Intestinal Absorptivity |
| GIAO | Gage Invariant Atomic Orbital |
| GIAO | Gage-including Atomic Orbital |
| GIAO | Gage-independent Atomic Orbital |
| GIAXRD | Grazing Incidence Angle X-ray Diffraction |
| GIC | Graphite Intercalation Compound |
| GICS | Grants Information And Control System |
| GID | Grazing Incidence Diffraction |
| GIF | Graphic Image Format |
| GIFT | Gamete Intrafallopian Transfer |
| GILD | Gas Immersion Laser Doping |
| GIME | Gas Injection Membrane Extraction |
| GIMS | Grazing Incidence Moessbauer Spectroscopy |
| GINC | Global Information Network On Chemicals |
| GIOS | Generalized Infinite Order Sudden |
| GIP | Gastric Inhibitory Polypeptide |
| GIP | Glucose-dependent Insulinotropic Polypeptide |
| GIPM | Ground State Inversion Potential Method |
| GIPM/D | Ground State Inversion Potential Method Including Diffraction |
| GIPME | Global Investigation Of Pollution In The Marine Environment |
| GIPOF | Graded-Index Plastic Optical Fiber |
| GIPQ | Gage Invariant Periodic Quantization |
| GIPT | Granular Injection Paint Technology |