| Abbreviation | Definition |
|---|---|
| ECPX | ECC America |
| ECQX | Engineered Carbons |
| ECQX | Engineered Carbons Incorporated |
| ECR | East Central Railway |
| ECRL | East Coast Rail Line |
| ECRL | East Coast Rail Link |
| ECRX | Econo-Rail Corporation |
| ECRZ | Conrail (Norfolk Southern) |
| ECRZ | Consolidated Rail Corporation |
| ECTB | East Chattanooga Belt Railway |
| ECUX | Exxon Chemical Americas |
| ECUX | Exxon Chemical Americas (Exxon-Mobil Corporation) |
| ECXX | ECDC Environmental |
| ECXX | ECDC Environmental L.C. |
| EDCX | EDC |
| EDCX | El Dorado Chemical Company |
| EDEX | Empire District Electric |
| EDEX | Empire District Electric Company |
| EDGX | Alliant Energy |
| EDGX | Wisconsin Power and Light Company |