| Abbreviation | Definition |
|---|---|
| GFR | Grand Forks Railway Company |
| GFR | Grand Funk Railroad |
| GFRR | Georgia and Florida Railroad |
| GFRR | Georgia and Florida Railroad Company |
| GFSX | GATX Capital Corporation |
| GFSX | General American Marks (GATX Corporation) |
| GGCX | Georgia Gulf Corporation (Plaquemine Division) |
| GGCX | Georgia Gulf Corporation-Plaquemine Div |
| GGIX | Garvey International (Garvey Grain Division) |
| GGIX | Garvey International Garvey Grain Division |
| GGMX | Golden Gate Railroad Museum |
| GGPX | General American Marks (GATX Corporation) |
| GGPX | General American Marks Company |
| GGR | Galt & Guelph Railway |
| GGRR | Gibsonville Garden Rail Road |
| GGRR | Guelph & Goderich RailRoad |
| GGS | Georgia Great Southern Division - South Carolina Central Railroad Company |
| GGS | South Carolina Central Railroad (Georgia Great Southern Division) |
| GGSU | Seacor Island Lines |
| GHBX | G. Heileman Brewing |