| Abbreviation | Definition |
|---|---|
| GRT | Grand River Transit |
| GRT | Gross Registered Tonnage |
| GRT | Group Rapid Transit |
| GRTA | Georgia Regional Transportation Authority |
| GRTCC | Ghana Road Transport Coordinating Council |
| GRTM | Glen Rose Transportation Management |
| GRV | Green Ray Vehicles |
| GS | Gelande Sport |
| GS | Goes Slow |
| GS | Grand Sports |
| GS | Gravel Street |
| GS | Great Sedan |
| GSLV | A Geosolar Satellite Launch Vehicle |
| GSLV | Generally Sea Loving Vehicle |
| GSLV | Geo Satellite Launch Vehicle |
| GSLV | Geo stationary Launch Vehicle |
| GSLV | Geosolar Satellite Launch Vehicle |
| GSLV | Geostationary Satellite Launch Vehicle |
| GSLV | Geosynchronous Satellite Launch Vehicle |
| GSM | Gilera Super Motard |