| Abbreviation | Definition |
|---|---|
| ETAC | Environmental Technical Advisory Committee |
| ETAC | Environmental Technical Applications Center |
| ETAD | Environmental Technology Advancement Directorate |
| ETAP | Environmental Technologies Action Plan |
| ETAP | Estacion de Tratamiento de Agua Potable |
| ETC | Environmental Technology Control |
| ETC | Environmental Training Center |
| ETCW | Early twentieth century warming |
| ETEC | Eco Technology Exhibition Centre |
| ETF | External Tailings Facility |
| ETFC | Environmental Trade Fair and Conference |
| ETGI | Environmental Transport Group Inc |
| ETI | Environmental Technology Inc |
| ETI | Environmental Testing Inc |
| ETI | Environmental Training Institute |
| ETIA | Environmental Technology and International Affairs |
| ETIA | Environmental Technology International Affairs |
| ETIC | Environmental Technology Industry Cluster |
| ETIC | Environmental Teratogen Information Center |
| ETLS | Environmental Tort Litigation Section |