| Name | Meaning | Gender | Origin |
|---|
| Sienna | Reddish orange-brown | Female | Italian |
| Simba | Lion | Female | Swahili |
| Simone | Listening | Female | Hebrew |
| Skittles | | Unisex | Hebrew |
| Skyla | The sky | Female | American English |
| Slim | Slender in proportion to height. | Unisex | English |
| Smoky | | Unisex | Hebrew |
| Sofia | Wisdom | Female | Greek |
| Solo | | Unisex | Hebrew |
| Sonic | Approaching the speed of sound, fast-paced | Unisex | English |
| Sophie | Wisdom | Female | Greek |
| Sparky | Animated, lively. | Unisex | English |
| Speedy | Rapid motion, swift. | Unisex | English |
| Spider | An eight legged insect | Unisex | English |
| Spud | Slang for potato. | Unisex | English |
| Spunky | Spirited, plucky. | Unisex | English |
| Squirt | Slang for a small person | Unisex | English |
| Starlight | | Unisex | Hebrew |
| Stretch | To extend to full length. | Unisex | English |
| Stumpy | A short, thickset person | Unisex | English |
| Styx | Myth Name (A River Of The Underworld) | Unisex | English |
| Sugar | A sweet powder from sugar cane. Slang for sweetheart. | Female | English |
| Sweetie | Sweetheart. | Unisex | English |
| Sydney | Wide meadow | Female | English |
| Taffy | Beloved | Female | Welsh |
| Tasha | (Christ's) birthday | Female | Latin |
| Teresa | Harvester | Female | Greek |
| Tiny | Extremely small | Unisex | English |
| Titan | Powerful big man | Unisex | Greek |
| Titania | Uncertain, perhaps of the Titans | Female | Latin |