| Name | Meaning | Gender | Origin |
|---|
| Jelly | | Unisex | Hebrew |
| Jemma | Italian, precious stone | Female | Spelling |
| Jerold | Variant of Gerald Rules by the spear.
| Male | |
| Jesusa | Named for Jesus
| Female | |
| Joaquin | Abbreviation of the Hebrew name Jehoichin meaning Jehovah has established. Joaquin Miller the colorful 19th century poet-adventurer of the American west.
| Male | Spanish |
| Joellen | Jehovah is God. Feminine of Joel.
| Female | |
| Jonah | Dove. In the bible Jonah was on board a ship God caused to sink: sailors traditionally use the name Jonah to personify someone who brings bad luck.
| Male | Hebrew |
| Jore | God will uplift
| Male | |
| Josephine | God will increase | Female | |
| Joshua | God is salvation
| Male | Hebrew |
| Jules | youthful; soft, downy | Male | |
| Julia | Youthful
| Female | Latin |
| Junior | Youthful person. Used to distinguish son from father where they have the same name | Male | Latin |
| Kactus | | Male | Hebrew |
| Kafir | | Male | Hebrew |
| Katrina | Greek, pure | Female | |
| Kattrina | Pure.
| Female | |
| Kayla | crown of laurels | Female | Arabic |
| Keene | Ancient.
| Male | |
| Keets | | Male | Hebrew |
| Keypie | | Unisex | |
| Kingsley Shackelbolt | | Unisex | |
| Kingston | From the king's village or estate King's field. King is one of several titles occasionally used as given names.
| Male | English |
| Kinsey | victorious prince | Female | English |
| Kissycat | | Unisex | Hebrew |