| Abbreviation | Definition |
|---|---|
| GR | George Reid |
| GR | Georgius Rex |
| GR | Gilbert Ramsay |
| GR | Grant Richter |
| GR | Gypsy Rose |
| GRD | Guru Ram Das, Sikh guru |
| GRI | Georgius Rex Imperator |
| GRRM | George R. R. Martin |
| GS | George Schmidt |
| GS | George Stanford |
| GS | Gordon Smith |
| GSH | George S. Halas, football coach, Chicago Bears |
| GSP | George Saint Pierre |
| GT | Gary Turner |
| GT | Grandpa Tony |
| GTM | Great Teacher Mishari |
| GTO | Great Teacher Onizaku |
| GTW | Grand Theft Walrus |
| GUB | Great Uncle Bob |
| GW | Garth Woodside |