| Name | Meaning | Gender | Origin |
|---|
| Saoirse | Freedom | Female | Gaelic |
| Saraid | Best | Female | Gaelic |
| Sasha | Defending men | Unisex | Greek |
| Sassy | Lively and spirited | Unisex | English |
| Scully | Town Crier | Male | English |
| Shadow | Shadow | Unisex | English |
| Shanley | Old hero | Female | Gaelic |
| Shannon | God is gracious | Female | Hebrew |
| Sheba | Daughter of an oath | Female | Hebrew |
| Shelby | A place where willows grow | Female | American English |
| Shorty | Of less than average size | Unisex | English |
| Sierra | Mountain range | Female | Spanish |
| Simba | Lion | Female | Swahili |
| Sinead | Praise | Female | English |
| Slim | Slender in proportion to height. | Unisex | English |
| Sloan | Fighter | Male | American English |
| Sloane | Fighter | Unisex | American English |
| Sophie | Wisdom | Female | Greek |
| Sorcha | Brightness, light | Female | Gaelic |
| Sparky | Animated, lively. | Unisex | English |
| Spencer | Someone who gives out goods | Male | French |
| Spike | A long, thick sharp-pointed piece of wood or metal | Male | English |
| Squirt | Slang for a small person | Unisex | English |
| Stumpy | A short, thickset person | Unisex | English |
| Sunny | Filled with sunlight | Male | English |
| Sweetie | Sweetheart. | Unisex | English |
| Tara | Crag | Female | Gaelic |
| Teddy | Gift of God | Male | Greek |
| Tierney | Lordly, noble | Male | Gaelic |
| Tiny | Extremely small | Unisex | English |