| Name | Meaning | Gender | Origin |
|---|
| Rusty | Rusty, full of rust | Unisex | American English |
| Sabre | | Unisex | Hebrew |
| Saffie | Spice | Unisex | English |
| Sailor | Sailor | Unisex | English |
| Salty | | Unisex | Hebrew |
| Sam | He is called god | Male | Hebrew |
| Sammy | His name is God | Unisex | Hebrew |
| Samson | Sun | Male | Hebrew |
| Sandy | Defending men | Male | Greek |
| Sasha | Defending men | Unisex | Greek |
| Sassy | Lively and spirited | Unisex | English |
| Scooby | | Unisex | Hebrew |
| Scott | Painted warrior | Male | English |
| Scotty | Painted warrior | Male | English |
| Scout | Observer | Unisex | American English |
| Shadow | Shadow | Unisex | English |
| Shaggy | Bushy and matted (hair), unkempt. | Unisex | English |
| Skippy | Master of a Ship | Unisex | American English |
| Smoky | | Unisex | Hebrew |
| Sniff | A short inhale through the nose. To savour or investigate a smell. | Unisex | English |
| Snoopy | | Unisex | Hebrew |
| Sparkle | To shine with animation | Unisex | English |
| Sparky | Animated, lively. | Unisex | English |
| Spike | A long, thick sharp-pointed piece of wood or metal | Male | English |
| Spot | After Data's cat on Star Trek: The Next Generation | Unisex | English |
| Starlight | | Unisex | Hebrew |
| Stevie | Crown | Unisex | Greek |
| Sunny | Filled with sunlight | Male | English |
| Sylvester | A forest | Male | Latin |
| Tank | A large metal container. A heavily armed combat vehicle | Unisex | English |