| Name | Meaning | Gender | Origin |
|---|
| Rusty | Rusty, full of rust | Unisex | American English |
| Ryan | Little King | Male | Gaelic |
| Sage | Aromatic herb | Unisex | English |
| Sailor | Sailor | Unisex | English |
| Sam | He is called god | Male | Hebrew |
| Samson | Sun | Male | Hebrew |
| Scamper | | Unisex | Hebrew |
| Scooby | | Unisex | Hebrew |
| Scooter | One who goes suddenly and speedily. | Unisex | English |
| Scotch | Scotch whiskey. | Unisex | English |
| Scott | Painted warrior | Male | English |
| Scout | Observer | Unisex | American English |
| Sebastian | Man from Sebaste | Male | Latin |
| Shadow | Shadow | Unisex | English |
| Shamus | Supplanter | Male | Hebrew |
| Shayne | God is gracious | Male | Hebrew |
| Sigmund | Protector | Male | German |
| Silver | Silver (the metal or colour) | Male | English |
| Simon | Listening | Male | Hebrew |
| Skip | Master of a Ship | Male | American English |
| Skippy | Master of a Ship | Unisex | American English |
| Slate | | Unisex | Hebrew |
| Smokey | A grayish blue colour. Slang for highway patrol officer | Unisex | English |
| Snickers | A brand of candy bar. | Unisex | English |
| Snoopy | | Unisex | Hebrew |
| Socks | Short stockings finishing above the ankle | Unisex | English |
| Spanky | | Unisex | Hebrew |
| Sparky | Animated, lively. | Unisex | English |
| Speedy | Rapid motion, swift. | Unisex | English |
| Spike | A long, thick sharp-pointed piece of wood or metal | Male | English |