FDOS
| Acronym | Definition |
|---|---|
| FDOS | First Day of Service |
| FDOS | First Day of School |
| FDOS | First Day of Summer |
| FDOS | Flooder Denial of Service |
| FDOS | Floppy Disk Operating System |
| FDOS | Florida Department of State |
| FDOS | First Day of Spring (Rita's promotion) |
| FDOS | From Date of Service (various states) |
| FDOS | Finest Depth of Sort (US Postal Service) |
| FDOS | Fixed Disk Operating System |