| Name | Meaning | Gender | Origin |
|---|
| Shirley | country meadow | Female | English |
| Sid | | Unisex | |
| Sidney | Saint Denis | Female | |
| Silva | Forest | Unisex | Latin |
| Silvester | Forest | Unisex | English |
| Silvia | from the woods | Female | Latin |
| Silvio | from the sitcom The Sopranos | Male | Italian |
| Sloth | | Unisex | Hebrew |
| Sly | One who is cunning, tricky and crafty. | Male | English |
| Speckles | | Unisex | Hebrew |
| Spot | after Data's cat on Star Trek: The Next Generation | Male | |
| Spotty | Marked with spots | Unisex | |
| Squirrel | | Unisex | |
| Stella | a star | Female | Latin |
| Stella | a star | Female | Latin |
| Streak | | Unisex | |
| Sylvester | A cartoon cat that tried to eat the bird character Tweety. He was a black and white cat.
| Male | Latin |
| Sylvia | from the forest | Female | Latin |
| Sylvie | from the forest | Female | |
| Tabitha | gazelle, roe-buck | Female | Aramaic |
| Tex | Of Texas | Male | English |
| Theodore | gift of God | Male | Greek |
| Thor | Viking mythology: the ruler of the weather | Male | Norse |
| Tiger | A large, striped, carnivorous mammal from Asia. | Male | Animal |
| Tiger | A large, striped, carnivorous mammal from Asia. | Male | Animal |