| Name | Meaning | Gender | Origin |
|---|
| Jill | youthful | Female | English |
| Jinx | Charm, Spell | Female | Latin |
| Johnny | the Lord is gracious | Male | English |
| Jones | God Will Bring | Male | Welsh |
| Jonesy | | Unisex | Hebrew |
| Josie | From Josephine - She shall add. | Female | English |
| Kallibunker | | Unisex | Hebrew |
| Kari | curly hair | Male | Norse |
| Karma | Fate or destiny (Hinduism and Buddhism) | Female | Hindi |
| Katnip | | Unisex | Hebrew |
| Kennedy | misshapen head | Female | Irish |
| Kitty | Variant of Katherine. Pure.
| Female | English |
| Kitty | Variant of Katherine. Pure.
| Female | English |
| Kitty | Variant of Katherine. Pure.
| Female | English |
| Kitty Perry | | Unisex | |
| Kittycat | | Male | Hebrew |
| Koko | stork | Female | Japanese |
| Koolio | | Unisex | |
| Krazy Kat | | Unisex | Hebrew |
| Lady Jane | | Unisex | |
| Larry | Abbreviation of Lawrence or Laurence often used as an independent name.
| Male | English |
| Leo | Lion.
| Male | Latin |
| Lewis | Renowned fighter. Form of Louis.
| Male | English |
| Lilith | character in Cheers | Female | Assyrian |
| Lionel | Cousin of Lancelot
| Male | Latin |