| Klassenkasper | class clown |
| klassenbasiert | class-based |
| Klassenkampf | class conflict |
| Klassenkamerad | classmate |
| Klassenlehrer | class teacher homeroom teacher |
| Klassenzimmer | classroom schoolroom |
| klassenlos | classless |
| Klassenarbeit | class test exam |
| Klassenfahrt | school trip |
| Klassenraum | classroom |
| Klassiker | classic |
| Flaschenwasser | bottled water |
| Kassenknüller | blockbuster |
| Gassenhauer | popular melody popular song |
| Krankenkasse | health maintenance organization public health insurance |
| Straßenkämpfer | streetfighter |
| Flossenfüßer | pinniped |
| Linsenraster | lenticular |
| Klagender | wailer |
| Klapperkiste | jalopy |