| Name | Meaning | Gender | Origin | 
|---|
| Jace | Hebrew, the Lord is salvation | Male | Hebrew | 
| Jack | after the Georgetown University mascot, Jack the Bulldog | Male | English | 
| Jack | From John - God's gracious gift | Male | English | 
| Jax | God has been gracious: has shown favor. Based on John or Jacques.
 | Male | Modern | 
| Jefferson | son of Jeffrey | Male | English | 
| Jeremy | God will uplift, appointed by God | Male | English | 
| Jerome | sacred name | Male | Greek | 
| Jerry | after Jerry Garcia, The Grateful Dead | Male | English | 
| Jesse | wealthy | Male | Hebrew | 
| Jim | supplanter | Male | English | 
| Jimmy | supplanter | Male | English | 
| John | God is merciful | Male | Hebrew | 
| 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 | 
| Jonathan | God gives | Male | Hebrew | 
| Jordy | Flow, Descend | Unisex | English | 
| Julius | after Julius Caesar | Male | Latin | 
| Kazooie |  | Unisex | Hebrew | 
| Kelvin | name of a river; from the narrow river | Male | Scottish | 
| Kevin | handsome | Male | Irish | 
| Kirby | church settlement | Male | Norse | 
| Kyle | A place-name referring to the narrows: a wood or a church.
 | Male | Scottish | 
| Laser |  | Male | Hebrew | 
| Laszlo | after the character in the movie Real Genius | Male | Hungarian | 
| Legolas | Tolkien, Lord of the Rings | Unisex |  | 
| Leia | Weary | Unisex | Hebrew |