| Name | Meaning | Gender | Origin |
|---|
| 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 |
| Scooter | One who goes suddenly and speedily. | Unisex | English |
| Scout | Observer | Unisex | American English |
| Shark | | Unisex | Hebrew |
| Shasta | Name of a Native American tribe | Female | Native American |
| Sheba | Daughter of an oath | Female | Hebrew |
| Sherry | The plains | Female | Hebrew |
| Shiloh | Gift for him | Unisex | Hebrew |
| Shorty | Of less than average size | Unisex | English |
| Skinny | | Unisex | Hebrew |
| Sky | Sky | Unisex | Norse |
| Skylar | Guarded | Female | Dutch |
| Smiley | | Unisex | Hebrew |
| Smokey | A grayish blue colour. Slang for highway patrol officer | Unisex | English |
| Snake | | Unisex | Hebrew |
| Solo | | Unisex | Hebrew |
| Sophie | Wisdom | Female | Greek |
| Spanky | | Unisex | Hebrew |
| Spider | An eight legged insect | Unisex | English |
| Spot | After Data's cat on Star Trek: The Next Generation | Unisex | English |
| Spud | Slang for potato. | Unisex | English |
| Stinky | | Unisex | Hebrew |
| Sue | Lily | Female | Hebrew |
| Sugar | A sweet powder from sugar cane. Slang for sweetheart. | Female | English |
| Suzy | Lily | Female | Hebrew |
| Tank | A large metal container. A heavily armed combat vehicle | Unisex | English |
| Taryn | King Of Rocky Hill. Variant Of Tarynn. | Female | American English |
| Tarzan | White skin | Unisex | Literary |