| Festbettreaktor | fixed bed reactor |
| Brutreaktor | fast breeder fast breeder reactor |
| Fusionsreaktor | fusion reactor |
| festtreten | tread |
| Festmeter | cubic metre cubic meter |
| Destruktor | destructor |
| Restaurator | restorer |
| Kettenreaktion | chain reaction |
| Atomreaktor | nuclear reactor |
| Kernreaktor | nuclear reactor |
| Distraktor | distracter |
| Störfaktor | disruptive element |
| Festredner | celebrant |
| Festwertspeicher | read-only memory |
| festgeklemmt | jammed |
| festgesetzt | stuck |
| feststecken | lodge |
| festkehren | corner prevent stop |
| festsetzen | define determine fix set arrest detain put away stick collect settle squat entrench occupy |
| Gestotter | stammering |