| Abbreviation | Definition |
|---|---|
| FLR | FaiLuRe |
| FLR | FLaRe |
| FLS | FLight Surgeon |
| FLSC | Flexible Linear Shaped Charge |
| FLT | FLighT |
| FLT | FLoaTing |
| FLTR | FiLTeR |
| FLTSATCOM | FLeeT SATellite COMunications |
| FLUOR | FLUORescent |
| FLW | Fellows, California, TACAN Station |
| FM | Failure Mechanics |
| FM | Failure Mode |
| FM | Flight Model |
| FM | Flight Module |
| FM | Furnace Module |
| FM/FM | Frequency Modulation/Frequency Multiplexing |
| FM/PM | Frequency Modulation/Phase Modulation |
| FMA | Failure Mode Analysis |
| FMA | First Mission Available |
| FMAHTS | Flight Manifest And Hardware Tracking System |