| Name | Meaning | Gender | Origin |
|---|
| Sebastian | Man from Sebaste | Male | Latin |
| Shadow | Shadow | Unisex | English |
| Shakespeare | Brandish spear | Unisex | English |
| Shelby | A place where willows grow | Female | American English |
| Sherlock | With cropped hair | Male | English |
| Sherman | One who shears cloth | Male | English |
| Shorty | Of less than average size | Unisex | English |
| Sigmund | Protector | Male | German |
| Silver | Silver (the metal or colour) | Male | English |
| Simba | Lion | Female | Swahili |
| Simon | Listening | Male | Hebrew |
| Skeeter | | Unisex | Hebrew |
| Skipper | Master of a Ship | Male | American English |
| Skippy | Master of a Ship | Unisex | American English |
| Skooter | | Unisex | Hebrew |
| Sleepy | | Unisex | Hebrew |
| Smidge | | Unisex | Hebrew |
| Smokey | A grayish blue colour. Slang for highway patrol officer | Unisex | English |
| Snickers | A brand of candy bar. | Unisex | English |
| Sniper | A skilled shooter who spots targets from a concealed place. | Unisex | English |
| Snoop | To pry into the private affairs of others | Unisex | English |
| Snoopy | | Unisex | Hebrew |
| Socks | Short stockings finishing above the ankle | Unisex | English |
| Socrates | Uncertain meaning | Male | Greek |
| Sol | Peace | Male | Hebrew |
| Sonny | Son | Male | English |
| 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 |
| Spirit | Part of the human being associated with the mind. Vigorous or animated state - spirited. Also distilled alcohol. | Unisex | English |