| Abbreviation | Definition |
|---|---|
| GRAS | Giant Robot Appreciation Society |
| GROL | Green Ring Of Life |
| GSFG | Gigantic Science Fiction Geeks |
| GSS | Gartsides Secret Stuff |
| GSS | Geneon Signature Series |
| GSSA | Global Security and Stability Agency |
| GST | Galactic Standard Time |
| GST | Grenades, Snarks, & Teleporters |
| GT | Galactic Terran |
| GT | Goten and Trunks |
| GUBU | Grotesque, Unbelievable, Bizarre, and Unprecedented |
| GUN | Guardian Unit of Nations |
| GURPS | Generic Universal RolePlaying System |
| GUTS | Generic Universal Tactical System |
| GVN | Global Vampire Network |
| GW | Galaxy War |
| GWC | Great World City |
| GWL | Great Warriers Land |
| GWTV | Gundam Wing: The Virus |
| HAD | Hear All Dragons |