| Acronym | Definition |
|---|
| FDL | Free Documentation License |
| FDL | Fond Du Lac (Amtrak station code; Fond Du Lac, WI) |
| FDL | Fond du Lac (Wisconsin, US) |
| FDL | Fleur-de-Lis (symbol) |
| FDL | FireDogLake (website) |
| FDL | Fonds de Développement Local (French: Local Development Fund; Madagascar) |
| FDL | Frontier Development Lab (US NASA) |
| FDL | Facility Data Link |
| FDL | Facilities Data Link |
| FDL | File Definition Language |
| FDL | Fiber Delay Line |
| FDL | Federal Direct Loan (US Department of Education) |
| FDL | Flexor Digitorum Longus |
| FDL | Forward Defense Line |
| FDL | Fighter Data Link |
| FDL | Flight Dynamics Laboratory |
| FDL | Faculdade de Direito de Lisboa (Lisbon Law School; Portugal) |
| FDL | Fieldbus Data Link |
| FDL | Flight Deck Lighting (US Navy) |
| FDL | France Divertissement Loisir (French: France Entertainment Leisure) |
| FDL | Fuselage Datum Line (Airbus Aircraft manual) |
| FDL | Final Determination Letter |
| FDL | Fast Deployment Logistics |
| FDL | Forensic Document Lab |
| FDL | Fardeloup Dynamisme Loisirs (French sports association) |
| FDL | FAAD Data Link |
| FDL | Forms Definition Language |
| FDL | Finite Distributed Lag |
| FDL | Forward Defended Localities |
| FDL | Fall Down Laughing |
| FDL | Fermentation Development Laboratory |
| FDL | Florida Drumline (University of Florida) |
| FDL | Forum on Specification, Verification and Design Languages |
| FDL | Focus Design Location |
| FDL | Failure Derivation Location |