| Acronym | Definition |
|---|
| FEN | Fédération de l'Education Nationale (French: Federation of National Education) |
| FEN | Family Education Network (various organizations) |
| FEN | Fast Ethernet Network |
| FEN | Far-End |
| FEN | Financial Economics Network |
| FEN | Fédération des Étudiants Nationalistes (French: Federation of Student Nationalists) |
| FEN | Far East Network |
| FEN | Fédération des Étudiants Neuchâtelois (French: Neuchâtel Students Federation; Neuchâtel, Switzerland) |
| FEN | Fashion Europe Net (est. 2006; various locations) |
| FEN | Free-Net Erlangen/Nuernberg |
| FEN | Free Expression Network |
| FEN | Forsythe Edwards Notation (chess) |
| FEN | Florida Educational Negotiators |
| FEN | Fluids, Electrolytes, Nutrition |
| FEN | Field-Equivalent-Noise |
| FEN | Field Engineering Notice |
| FEN | Female Executives Network |
| FEN | Failure Event Notification |
| FEN | Familial Endocrine Neoplasia |