| Name | Meaning | Gender | Origin |
|---|
| Sox | Short stockings finishing above the ankle | Unisex | |
| Sox | Short stockings finishing above the ankle | Unisex | |
| Spark | | Unisex | |
| Specs | | Unisex | Hebrew |
| Splash | To cause fluid to scatter in flying masses. To display very noticeably. | Unisex | |
| Spock | | Unisex | |
| Sport | One who accepts difficult situations well. | Unisex | |
| Sprout | | Unisex | Hebrew |
| Spuds | | Unisex | Hebrew |
| Spur | | Unisex | Hebrew |
| Spy | | Unisex | Hebrew |
| Squid | | Unisex | |
| Steed | | Unisex | |
| Steele | | Unisex | |
| Sting | To pierce painfully with a sharp point. | Unisex | |
| Stitch | after the character in the Lilo And Stitch cartoon | Unisex | |
| Styx | from Greek mythology, the river that formed the boundary between earth and the underworld | Unisex | |
| Suess | | Unisex | |
| Suggs | | Unisex | |
| Suze | | Unisex | Hebrew |
| Swan | | Unisex | Hebrew |
| Sweet | | Unisex | Hebrew |
| Swift | | Unisex | |
| Switch | | Unisex | |
| Tag | | Unisex | |