| Konfession | denomination |
| konfessionslos | nonsectarian |
| Konzession | concession admission licence |
| konfessionsfrei | nonsectarian |
| Konfektion | make manufacture ready-to-wear off-the-peg clothing off-the-rack clothing clothing industry |
| Konfusion | bewilderment |
| Konkussion | concussion |
| Konversion | conversion |
| Konfessionsloser | nonsectarian |
| Kontorsion | contortion |
| Konklusion | conclusion |
| Konvention | convention |
| Konvulsion | convulsion |
| Konzeption | conception |
| konzessiv | concessive |
| Profession | profession occupation trade |
| Koexpression | coexpression |
| Kompression | compression |
| Obsession | obsession |
| Kernfission | nuclear fission |