- KO
- KO punch
- koala
- koala bear
- koan
- Koasati
- kob
- Kobe
- Kobenhavn
- kobo
- Kobuk Valley National Park
- Kobus
- Kobus kob
- Kobus leche
- Koch
- Kochia
- Kochia scoparia
- KOd
- Kodiak
- Kodiak bear
- Kodiak Island
- Koellia
- Koestler
- Kogia
- Kogia breviceps
- Kogia simus
- kohl
- kohleria
- kohlrabi
- Koine
- koinonia
- kok-saghyz
- kok-sagyz
- Kokka
- Kokka Shinto
- kokoi venom
- Kol Nidre
- kola
- kola nut
- kola nut tree
- Kola Peninsula
- Kolam
- Kolami
- Kolkata
- kolkhoz
- kolkhoznik
- Kolkwitzia
- Kolkwitzia amabilis
- Koln
- Kolonia
- Komi
- Komodo dragon
- Komodo lizard
- komondor
- Kon Tiki
- Konakri
- Kong the Master
- Kongfuze
- Kongo
- konini
- Konoe
- Konoye
- Konqueror
- Konrad Adenauer
- Konrad Lorenz
- Konrad von Gesner
- Konrad Zacharias Lorenz
- Konstantin Sergeevich Alekseev
- Konstantin Sergeyevich Stanislavsky
- Konstantin Stanislavsky
- koodoo
- kook
- kookaburra
- kookie
- kooky
- Koopmans
- kopeck
- kopek
- kopiyka
- kopje
- Kopliks spots
- koppie
- kor
- Koran
- Koranic
- Korbut
- Korchnoi
- Korda
- Kordofan
- Kordofanian
- Kore
- Korea
- Korea Bay
- Korea Strait
- Korean
- Korean lawn grass
- Korean lespedeza
- Korean Peninsula
- Korean Strait
- Korean velvet grass
- Korean War
- Korinthos
- Korsakoffs psychosis
- Korsakoffs syndrome
- Korsakovs psychosis
- Korsakovs syndrome
- koruna
- Korzybski
- kos
- Kosciusko
- Kosciuszko
- kosher
- Kosovo
- Kosteletzya
- Kosteletzya virginica
- Kota
- Kotar
- Kotex
- koto
- koto player
- Kotoko
- kotow
- koudou
- koumiss
- Koussevitzky
- Kovna
- Kovno
- Koweit
- kowhai
- kowtow