| Klirrfaktor | distortion factor |
| Störfaktor | disruptive element |
| Formfaktor | form factor |
| Biofaktor | biofactor |
| Primfaktor | prime factor |
| Kernreaktor | nuclear reactor |
| Korrektor | proofreader |
| Inputfaktor | factor of production |
| Faktor | factor merchant |
| Kontrafaktur | contrafact |
| Atomreaktor | nuclear reactor |
| Brutreaktor | fast breeder fast breeder reactor |
| Distraktor | distracter |
| Kontraktur | contracture |
| Reaktor | reactor |
| Refraktor | refracting telescope refractor |
| Traktor | tractor |
| Viertakter | four-stroke engine |
| Direktor | manager director headmaster principal senior vice president |
| Liktor | lictor |