| Ikonodulie | iconodulism iconoduly |
| Ikonografie | iconography |
| Ikonolatrie | iconolatry |
| Ikonostase | iconostasis |
| Ökonomie | economy |
| Ikonoklast | iconoclast |
| Ikone | icon |
| Kondylom | genital wart |
| Konfutse | Confucius |
| Koniotomie | cricothyrotomy |
| Konoid | conoid |
| konfuse | confuse |
| Konkubine | concubine |
| Konsole | console |
| Konsul | consul |
| Konsulat | consulate |
| Kontrolle | inspection control |
| konvulsiv | convulsive |
| Ökoenergie | green energy green power |
| Ökonometrie | econometrics |