| Name | Meaning | Gender | Origin |
|---|
| Sasha | Defending men | Unisex | Greek |
| Sasquatch | Has extra toes and hence is a bigfoot | Unisex | English |
| Sassy | Lively and spirited | Unisex | English |
| Satan | The Devil and adversary of God | Unisex | English |
| Saturn | Sixth and second largest planet away from the Sun. | Unisex | English |
| Scooby | | Unisex | Hebrew |
| Scooter | One who goes suddenly and speedily. | Unisex | English |
| Shark | | Unisex | Hebrew |
| Snuffles | | Unisex | Hebrew |
| Stretch | To extend to full length. | Unisex | English |
| Suede | Swedish | Unisex | English |
| Tank | A large metal container. A heavily armed combat vehicle | Unisex | English |
| Tex | Of Texas | Unisex | English |
| Thunder | Stormy Tempered | Unisex | English |
| Titan | Powerful big man | Unisex | Greek |
| Tracey | Thracius' place | Unisex | English |
| Trojan | | Unisex | Hebrew |
| Wookie | | Unisex | Hebrew |