| Konventikel | conventicle |
| Konventionen | decorum |
| Konvention | convention |
| konventionell | conventional |
| Konvent | convent |
| Konvertit | convert |
| Konnetabel | constable |
| kongenial | congenial |
| kongenital | congenital |
| konvenient | convenient |
| konvenieren | be suitable |
| konvertieren | convert |
| Fonetiker | phonetician |
| Kosmetiker | cosmetician |
| Konterbier | hair of the dog |
| Konvervative | conservative |
| Konvexität | convexity |
| Konvexlinse | convex lens |
| Konzertina | concertina |
| Konzetti | extended metaphor |