| # | Name | Origin | Meaning | Gender | |
|---|---|---|---|---|---|
| 141 | Januarius | Polish | Born in January. | M | |
| 142 | Jarek | Polish | Born in January. | M | |
| 143 | Jasia | Polish | Polish form of Joanna: God is gracious. | F | |
| 144 | Jedrek | Polish | A strong man. Variant of Andrew. | M | |
| 145 | Jedrick | Polish | A strong man. Variant of Andrew. | M | |
| 146 | Jedrik | Polish | Strong. | M | |
| 147 | Jedrus | Polish | Strong. | M | |
| 148 | Jeny | Polish | Polish form of George 'farmer'. | M | |
| 149 | Joanka | Polish | Polish form of Joanna: God is gracious. | F | |
| 150 | Jolanta | Polish | Violet. | F | |
| 151 | Josep | Polish | Polish form of Joseph 'God shall add'. | M | |
| 152 | Kaleen | Polish | A flower name. | F | |
| 153 | Kaleena | Polish | A flower name. | F | |
| 154 | Kalena | Polish | A flower name. | F | |
| 155 | Kalene | Polish | A flower name. | F | |
| 156 | Kalina | Polish | A flower name. | F | |
| 157 | Kamilla | Polish | Ceremonial attendant. | F | |
| 158 | Kamillra | Polish | Ceremonial attendant. | F | |
| 159 | Kasienka | Polish | Pure. | F | |
| 160 | Kaska | Polish | Pure. | F | |