| Name | Meaning | Gender | Origin |
|---|
| Ian | Form of John | Male | Scottish |
| Iggy | Latin, fiery | Male | Latin |
| Jack | after the Georgetown University mascot, Jack the Bulldog | Male | English |
| Jack | From John - God's gracious gift | Male | English |
| Jacob | The supplanter, held by the heel | Male | Hebrew |
| Jake | From Jacob - To fill the place of another | Male | Hebrew |
| James | From Jacob - To fill the place of another, supplanter. | Male | English |
| Jason | the Lord is salvation | Male | Hebrew |
| Jay | jaybird | Male | Latin |
| Jeffrey | pledge of peace | Male | Spelling |
| Jeremy | God will uplift, appointed by God | Male | English |
| Jesse | wealthy | Male | Hebrew |
| 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 |
| John | God is merciful | Male | Hebrew |
| Jonathan | God gives | Male | Hebrew |
| Jordan | The descending river, to flow | Male | Hebrew |
| Joseph | God will increase | Male | Hebrew |
| Joshua | God is salvation
| Male | Hebrew |
| Jules | youthful; soft, downy | Male | |
| Julian | Jove's child. Form of Julius and family clan name of several powerful Roman emperors. Biblical Roman centurion Julius saved Paul's life during a hazardous voyage
| Male | English |
| Justin | just, true | Male | Latin |
| Justus | Just | Male | Roman |
| Kai | Fire
| Male | Hawaiian |
| Kaiden | Fighter | Unisex | American |
| Kameron | Scottish surname, crooked nose | Male | Spelling |