| Name | Meaning | Gender | Origin |
|---|
| 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 | |
| Smudge | A blotch or smear | Male | |
| Snicker | | Unisex | Hebrew |
| Snickers | A brand of candy bar. | Unisex | |
| Snickers | A brand of candy bar. | Unisex | |
| Snowball | | Unisex | |
| Socks | Short stockings finishing above the ankle | Unisex | |
| Sox | Short stockings finishing above the ankle | Unisex | |
| Sox | Short stockings finishing above the ankle | Unisex | |
| Sparky | Animated, lively. | Unisex | |
| Speckles | | Unisex | Hebrew |
| Splotch | An irregularly shaped spot | Unisex | |
| Spot | after Data's cat on Star Trek: The Next Generation | Male | |
| Spotty | Marked with spots | Unisex | |
| Squeaky | | Unisex | |
| Squirrel | | Unisex | |
| Streak | | Unisex | |
| Stripes | | Unisex | |
| Sundae | | Unisex | |
| Sushi | Raw fish. | Unisex | |
| Sushi | Raw fish. | Unisex | |
| Thunder | Sound produced from lightning | Unisex | |
| Thunder | Sound produced from lightning | Unisex | |