| EFF | Ecology of Freshwater Fish 
| Others |
| EFF | Economic Freedom Fighter
| Others |
| EFF | Economic Freedom Fighters
| Others |
| EFF | Education Freedom Fighter
| Others |
| eff | effective
| Others |
| EFF | Eject Fast Forward
| Others |
| EFF | Electron Force Field
| Others |
| EFF | Electronic Font Foundry
| Others |
| EFF | Electronic Freedom Foundation
| Others |
| EFF | Electronic Frontier
| Others |
| EFF | Electronic Frontier Foundation
| Others |
| EFF | Electronic Frontiers Forum
| Others |
| EFF | Electronic Frontiers Forums
| Others |
| EFF | Electronics Frontier Foundation
| Others |
| EFF | Elite Federation Force
| Others |
| EFF | Emotion File Finish
| Others |
| EFF | Engine Effects File
| Others |
| EFF | Engine File Format
| Others |
| EFF | English First Foundation
| Others |
| EFF | Enhanced File Format
| Others |
| EFF | Equalized Frequency Flow
| Others |
| EFF | Equipped For the Future
| Others |
| EFF | Ethical Fashion Forum
| Others |
| EFF | European Fisheries Fund
| Others |
| EFF | European Founders Fund
| Others |
| EFF | European Franchise Federation
| Others |
| EFF | Exclusive Formula Feeding
| Others |
| EFF | Experimental Film Festival
| Others |
| EFF | Experimental Forecast Facility
| Others |
| EFF | Extended Font Format
| Others |
| EFF | Extended Format File
| Others |
| EFF | Extended Frame Format
| Others |
| EFF | Extended Fund Facility
| Others |
| EFF | Extensible Flat File
| Others |
| EFF | External Financing Fund
| Others |