The circular definition is one that uses the terms being defined as a part of the definition or assumes a prior understanding of the term being defined.
kickoff
kiddie
kiddo
kidnap
kidnapper
kidnapping
kidney
kill
killer
killing
kiln
kilo
kilobyte
kilogram
kilometer
kilowatt
kilt
kimono
kind
kindergarten
kindergartner
kindhearted
kindle
kindling
kindly
kindness
kindred
kinfolk
king
kingdom
kingfisher
kid
kiddie
kiddo
kidnap
kidnapper
kidnapping
kidney
kidney bean
kill
killer
killing
kiln
kilo
