| Katharer | Cathar |
| Katharerin | Cathar |
| Katarer | Qatari |
| Katarr | catarrh |
| Katheder | lectern |
| Katheter | catheter |
| Karthager | Carthaginian |
| Katarerin | Qatari |
| Kathole | papist |
| Katar | Qatar |
| Katarrh | catarrh |
| Kataster | land register cadastre |
| Kater | tomcat cat tom hangover |
| Katharina | Katherine Catharine Catherin Cathryn Katharine Katharyn |
| Katharsis | catharsis |
| Kathete | cathetus |
| Kathode | cathode |
| Athanor | athanor |
| Athener | Athenian |
| Äther | ether aether |