- Kr
- kraal
- Krafft-Ebing
- kraft
- kraft paper
- krait
- Krakatao
- Krakatau
- Krakatoa
- Krakau
- Krakow
- Krasner
- kraurosis
- kraurosis vulvae
- Kraut
- Krauthead
- Krebs
- Krebs citric acid cycle
- Krebs cycle
- Kreisler
- Kremlin
- krigia
- Krigia bulbosa
- Krigia dandelion
- krill
- kris
- Krishna
- Krishnaism
- Kriss Kringle
- Kriti
- Kroeber
- krona
- krone
- Kronecker
- Kronecker delta
- kroon
- Kropotkin
- Kroto
- krubi
- Kruger
- krummhorn
- Krung Thep
- Krupp
- Krypterophaneron
- krypton
- Krzysztof Kieslowski