K
- Franz Kafka — adjective Kafkaesque
- Mikhail Kalashnikov — the Avtomat Kalashnikova series of weapons, including the AK-47, the Kalashnikov Handheld Machine Gun or Ruchnoi Pulemet Kalashnikova obraztsa 1974g (RPK-74)
- Kamen Rider - The main protagonists of the various series in this Japanese TV franchise are named after their corresponding TV series.
- Ingvar Kamprad — the first two letters of IKEA, the home furnishings retailer he founded
- Gaetano Kanizsa, Italian psychologist — Kanizsa triangle
- Megan Kanka, abducted child - Megan's Law
- Moritz Kaposi, Hungarian dermatologist — Kaposi's sarcoma
- Theodore von Kármán — Karman line
- Anna Karenina
- Tadao Kashio — founder of Casio
- Yevgeny Kaspersky — Kaspersky Anti-Virus
- Shozo Kawasaki — founder, Kawasaki Heavy Industries
- Tomisaku Kawasaki — Kawasaki disease
- Lord Kelvin — kelvin, unit of thermodynamic temperature
- John F. Kennedy — John F. Kennedy International Airport, John F. Kennedy Center for the Performing Arts, Kennedy Center Honors, John F. Kennedy University
- Arthur Edwin Kennelly and Oliver Heaviside — Kennelly–Heaviside layer
- Paul Keres — Keres Defence
- Brian W. Kernighan — the third letter of the name awk, a computer pattern/action language, is taken from Kernighan
- John Kerr (physicist) — Kerr effect
- John Maynard Keynes — Keynesian economics
- Wilhelm Killing — Killing vector field
- Gustav Kirchhoff — Kirchhoff's Laws
- Donald Knuth — Knuth-Morris-Pratt algorithm
- Alexander Konstantinopolsky — Konstantinopolsky Opening
- Wladimir Peter Köppen — Köppen climate classification
- Alfried Krupp - founder of Krupp, now ThyssenKrupp
- Gerard Kuiper — Kuiper Belt
Read more about this topic: List Of Eponyms (A-K)