| Kiloparsec | kiloparsec |
| Gigaparsec | gigaparsec |
| Kildare | Kildare |
| Klopapier | loo paper toilet paper |
| Komparse | extra |
| Megaparsec | megaparsec |
| Parsec | parsec |
| Kilojoule | kilojoule |
| Kilokalorie | kilocalorie |
| Kilobyte | kilobyte |
| Kilogramm | kilogram kilogramme |
| Kilometer | kilometer kilometre |
| Kilowatt | kilowatt |
| Klopfen | knock |
| klopfen | knock beat tap thump |
| Klopfer | door knocker carpet beater |
| Kloppe | a kind of |
| Klops | meatball howler |
| Klöppel | clapper lace bobbin |
| Telophase | telophase |