| Abbreviation | Definition |
|---|---|
| GTL | Gas-to-Liquids |
| GTR | Genetic Testing Registry |
| GTRC | Georgia Tech Research Corporation |
| GTRE | Gas Turbine Research Establishment |
| GTRF | Glasgow Tissue Research Facility |
| GTRI | Georgia Tech Research Institute |
| GTRN | Global Tobacco Research Network (est. 2002) |
| GTRR | Georgia Tech Research Reactor |
| GVA | Gross Value Added |
| GVC | Global Value Chain |
| GVR | Grand View Research |
| HAAN | Heliophysical Astronomical Answers Now |
| HAAN | Heliophysical Astronomical Answers Now |
| HAARP | High Altitude Auroral Research Project |
| HAART | Highly active antiretroviral therapy |
| HABRIA | Holmium Amplifier for Breakthrough Research and Industrial Applications |
| HANNN | Healthy Ageing Network Northern Netherlands |
| HARC | Halon Alternatives Research Corporation |
| HARC | Houston Advanced Research Center |
| HARL | Hearing Aid Research Lab |