FESN
| Acronym | Definition |
|---|---|
| FESN | Family Education and Support Network (Oregon) |
| FESN | Federação dos Estudantes (Portuguese: Federation of Students; Brazil) |
| FESN | Friuli Experimental Seismie Network (Italian: Friuli Experimental Science Network; Friuli, Italy) |
| FESN | Florida Emergency Supplier Network |
| FESN | Far East Skate Network (Japan) |
| FESN | Florida Endangered Species Network (est. 2004) |