| Ikonoklasmus | iconoclasm |
| Ikonoklast | iconoclast |
| ikonoklastisch | iconoclastic |
| Ikonismus | iconism |
| Ökonomismus | economism |
| Ikonolatrie | iconolatry |
| Ikonostase | iconostasis |
| Konformismus | conformism |
| Kolorismus | colorism |
| Ökologismus | environmentalism |
| Ökotourismus | ecotourism |
| Alkoholismus | alcoholism |
| Kataklysmus | cataclysm |
| Mongolismus | mongolism |
| Ikonografie | iconography |
| Nikolaus | Saint Nicholas Santa Claus Nicholas Nickolas Nikolas Niccolas Nichalas Nichelas |
| König Artus | King Arthur |
| Konklave | conclave |
| Konklusion | conclusion |
| Konsensus | consensus |