| Name | Meaning | Gender | Origin |
|---|
| Skittles | | Male | |
| Sky | The expanse of air over the Earth | Female | Nature |
| Skye | sky, sheltering | Female | Scottish |
| Slate | | Male | |
| Slick | | Male | |
| Smith | blacksmith | Male | English |
| Smoke | | Unisex | |
| Smoke | | Unisex | |
| Smokey | A grayish blue colour. Slang for highway patrol officer | Male | |
| Smokey | A grayish blue colour. Slang for highway patrol officer | Male | |
| Smokey | A grayish blue colour. Slang for highway patrol officer | Male | |
| Snickers | A brand of candy bar. | Unisex | |
| Snickers | A brand of candy bar. | Unisex | |
| Snow | Frozen crystals that fall in soft, white flakes | Female | English |
| Snowball | | Unisex | |
| Snowdrop | | Male | |
| Snowflake | Single flake or crystal of snow. | Unisex | |
| Snowy | Covered with snow | Unisex | |
| Sooty | Covered with soot | Unisex | |
| Sorrel | reddish brown | Male | Botanical |
| Spade | | Unisex | |
| Spirit | Part of the human being associated with the mind. Vigorous or animated state - spirited. Also distilled alcohol. | Female | Word |
| Spooky | | Unisex | |
| Spot | after Data's cat on Star Trek: The Next Generation | Male | |
| Sprinkles | | Unisex | |