| Abbreviation | Definition |
|---|---|
| ETR | Electronic Title Registration |
| ETR | Electronic Trade Reference |
| ETR | Electronic Training Request |
| ETRAC | electronic THC Review and Compliance |
| ETRC | Electronic Text Research Center |
| ETRF | Electronic Test Request Form |
| ETRI | Electronics and Telecommunications Research Institute |
| ETRM | Electronic Technical Reference Manual |
| ETRR | Electronic Tax Return Reader |
| ETRS | Electronic Tourist Refund Scheme |
| ETRS | Electronic Transmission Range Selection |
| ETS | Electric Train Service |
| ETS | Electric Train Systems |
| ETS | Electronic Throttle System |
| ETS | Electronic Transaction Systems |
| ETS | Electronic Translator System |
| ETS | Electronic Truck Steering |
| ETS | Excited Triplet State |
| ETSC | Electronic Taxpayer Service Center |
| ETSI | Electronic Telecommunications Standard Institute |