| Acronym | Definition |
|---|
| FLS | Falls |
| FLS | Fundamentals of Laparoscopic Surgery |
| FLS | Food and Life Sciences (Cornell University; New York) |
| FLS | Flowserve Corporation (stock symbol) |
| FLS | Field-Level Security |
| FLS | Family Law Section (bar associations) |
| FLS | Français Langue Seconde (French: French Second Language) |
| FLS | Flood Statement (US FEMA) |
| FLS | Fame Login Server |
| FLS | Fixed Line Substitution |
| FLS | Fixed Length Structure |
| FLS | Flash |
| FLS | Fixed Line Services |
| FLS | Free Lance-Star (newspaper; Fredericksburg, VA) |
| FLS | Fundamentals of Land Surveying (various locations) |
| FLS | Fondation pour le Logement Social (French: Foundation for Social Housing) |
| FLS | Fitzroy Legal Service (Australia) |
| FLS | Forward Looking SONAR |
| FLS | Formation Locale de Sécurité (French: Local Security Training) |
| FLS | Fire Life Safety |
| FLS | Français Langue de Scolarisation (French: French Language Schooling) |
| FLS | Fédération Luxembourgeoise de Ski (French: Luxembourg Ski Federation; Luxembourg) |
| FLS | Front Line States |
| FLS | Full Length Shot (camera angle) |
| FLS | Folded Letter Sheet (philatelics) |
| FLS | First Level Support (helpdesk) |
| FLS | Foreign Language School |
| FLS | Florida Legal Services, Inc |
| FLS | Faculty Lecture Series (various schools) |
| FLS | Fibroblast-Like Synoviocyte |
| FLS | Fatty Liver Syndrome (hepatic lipidosis) |
| FLS | Fellow of the Linnean Society of London |
| FLS | Forensic Light Source |
| FLS | Fatigue Limit State |
| FLS | Flying Lab Software, LLC (video game company; Seattle, WA) |
| FLS | Family Life Specialist |
| FLS | Front Line Supervisor |
| FLS | Fiber Local Storage (Windows API) |
| FLS | Fluid Level Sensor |
| FLS | Forward Logistic Site |
| FLS | Frontal Lobe Syndrome |
| FLS | Flight Landing Strip |
| FLS | Summer Flounder |
| FLS | Flu-Like Syndrome |
| FLS | Fleet Logistics System |
| FLS | Flight Line Supervisor |
| FLS | Flashless (Powder) |
| FLS | Field Loadable Software (FAA) |
| FLS | Filthy Little Secret (band) |
| FLS | Fewleftstanding (band) |
| FLS | Field Logistics System |
| FLS | Free Lance Sales (website) |
| FLS | Fault Locator System |
| FLS | Fox Learning Systems (Pittsburgh, PA) |
| FLS | Fixed Light Source |
| FLS | Future Language Schools (Egypt) |
| FLS | Fuzzy Logical System |
| FLS | Fixed-Lag Smoothing |