| Acronym | Definition |
|---|
| FDU | Fairleigh Dickinson University |
| FDU | Fakultet Dramskih Umetnosti (Slovenian: Faculty of Dramatic Arts) |
| FDU | Flux Detector Unit (avionics) |
| FDU | Fudan University (Shanghai, China) |
| FDU | Force Design Update |
| FDU | Fratelli Dell'Uomo |
| FDU | Fiber Distribution Unit |
| FDU | Fleet Diving Unit (Canadian Forces) |
| FDU | Free Digital Universe (virtual world) |
| FDU | Bandundu, Zaire (airport code) |
| FDU | Font Deuglification (software) |
| FDU | Forest Development Unit (Canada) |
| FDU | Floppy Drive Unit |
| FDU | Frequency Doubling Unit |
| FDU | Fidelity Union Bancorp |
| FDU | Frequency Determining Unit |
| FDU | Force Deployment Update |
| FDU | Fade Down and Up |
| FDU | Faculty Development Unit (US Army; Ft Sam Houston, TX, USA) |
| FDU | Flight Duty Uniform |