| Abbreviation | Definition |
|---|---|
| GCEZ | Genstar Container Corporation |
| GCFX | Alstom Canada Transport |
| GCGX | Gulf Coast Grain |
| GCI | Grade Crossing Inventory |
| GCIX | Gabriel Chemicals |
| GCIX | Gabriel Chemicals Incorporated |
| GCLX | Gold Coast |
| GCLX | Gold Coast Limited |
| GCLZ | Global Chassis Leasing |
| GCLZ | Global Chassis Leasing Incorporated |
| GCMX | Gold Coast Chapter National Railway Historical Society |
| GCOX | Gold Coast Railroad Museum |
| GCP | Grade Crossing Predictor |
| GCPU | Genstar (BNSF Railway) |
| GCPU | Genstar Container Corporation |
| GCPX | Georgia Gulf Corporation (PVC Division) |
| GCPX | Georgia Gulf Corporation PVC Division |
| GCRD | Gulf Coast Rail District |
| GCRU | Gardner Cryogenics |
| GCRX | Grand Canyon Railway |