| Abbreviation | Definition |
|---|---|
| FCSN | Fire Controlman Seaman |
| FCT | Firepower Control Team |
| FCT | Foreign Comparative Testing |
| FCT | Fractional Component Thereof |
| FCTEC | Fuel Cell Test and Evaluation Center |
| FCU | Fire Control Unit |
| FCU | Forward Control Unit |
| FCU | Fuel Control Unit |
| FCX | Fire Coordination Exercise |
| FCZ | Forward Combat Zone |
| FD | Fire Direction |
| FD | Focused Dispatch (exercise) |
| FD | From Temporary Duty |
| FD | Fuertes Defensas (exercise) |
| FD | Functional Description |
| FD/SC | Failure Definition/Scoring Criteria |
| FDA | Food and Drug Administration |
| FDAA | Front Driving Axle Assembly |
| FDAAD | Field Derivative (Additive Authorizations) Database |
| FDAF | Free Dutch Air Force |