| Abbreviation | Definition |
|---|---|
| GBIT/S | Gigabits Per Second |
| GBOE | GigaBarrels of Oil Equivalent |
| GBPS | Gigabits Per Second |
| GBQ | Giga- Becquerels |
| GC | Galactic Coordinates |
| GDD | Growing Degree Day |
| GEV | Giga Electron Volts |
| GFA | Gross Floor Area |
| GGE | Gasoline Gallon Equivalent |
| GiB | GibiByte |
| GL | Gallon |
| GL | Gauge Length |
| GM | GigaMeter |
| Gm | gigametre |
| GM | Gram |
| GM | Grams |
| gm. | gram |
| GM-M | Gram-Meter |
| GMW | Gram Molecular Weight |
| GNH | Gross National Happiness (Bhutan) |