ETD
- Club of Four
- Electron-transfer dissociation
- Electronic Theses and Dissertations
- End-of-train device
- Estimated time of departure
- Estuary Transit District
- Etadunna Airstrip
- Etihad Airways
- Eustachian tube dysfunction
- Everhart–Thornley detector
- Exchange-traded derivative contract
- Exoplanet Transit Database
- Explosives trace detector
- Eye tracking on the International Space Station