| Name | Meaning | Gender | Origin |
|---|
| Sid | | Unisex | |
| Sidney | Saint Denis | Female | |
| Sierra | Dark Feminine of Ciaran.
| Female | Spanish |
| Sine | God Is Gracious | Unisex | Irish |
| Slate | | Male | |
| Snow | Frozen crystals that fall in soft, white flakes | Female | English |
| Snowy | Covered with snow | Unisex | |
| So | | Unisex | |
| Solomon | Wise and peaceful | Male | Hebrew |
| Spike | A long, thick sharp-pointed piece of wood or metal | Male | American |
| Splash | To cause fluid to scatter in flying masses. To display very noticeably. | Unisex | |
| Spring | spring season | Female | Word |
| Star | A celestial body that emits light. A famous performer. | Female | Word |
| Star | A celestial body that emits light. A famous performer. | Female | Word |
| Sting | To pierce painfully with a sharp point. | Unisex | |
| Storm | Storm
| Male | Word |
| Stratford | From The River Ford On The Street | Unisex | English |
| Styx | from Greek mythology, the river that formed the boundary between earth and the underworld | Unisex | |
| Summer | summer season | Female | Word |
| Sun | obedient | Female | Korean |
| Svetlana | star | Female | Russian |
| Syd | Variant of Sidney from St. Denis
| Male | |
| Sydney | from city of St. Denis | Female | |
| Taft | building site | Male | English |
| Tahoe | edge of the lake | Male | Native |