| Konkretum | concrete noun |
| konkret | concrete |
| Konkretion | concretion |
| Königtum | monarchy |
| Konkrement | calculus |
| Kontranym | contranym |
| Konzetti | extended metaphor |
| unkonkret | woolly |
| Konfetti | confetti |
| Kongress | congress convention |
| Konjektur | conjecture |
| Konsortium | consortium |
| Konsum | consumption |
| Kontinuum | continuum |
| Kontraktur | contracture |
| Kontur | contour outline |
| Kornkrebs | wheat weevil |
| Kornkreis | crop circle |
| Arboretum | arboretum |
| Mönchstum | monkhood |