| Name | Meaning | Gender | Origin |
|---|
| Rosie | Rose | Female | Latin |
| Rowdy | Boisterous. Western Nickname. | Unisex | English |
| Roxie | Star | Unisex | Persian |
| Roxy | Star | Female | Persian |
| Ruby | Red | Female | Latin |
| Rufus | Red | Male | Latin |
| Rusty | Rusty, full of rust | Unisex | American English |
| Sabre | | Unisex | Hebrew |
| Sade | Sweetly singing | Female | African |
| Sadie | Princess | Female | Hebrew |
| Sam | He is called god | Male | Hebrew |
| Samantha | Listener | Female | Aramaic |
| Sammy | His name is God | Unisex | Hebrew |
| Samson | Sun | Male | Hebrew |
| Sandy | Defending men | Male | Greek |
| Sasha | Defending men | Unisex | Greek |
| Sasquatch | Has extra toes and hence is a bigfoot | Unisex | English |
| Sassy | Lively and spirited | Unisex | English |
| Satan | The Devil and adversary of God | Unisex | English |
| Saturn | Sixth and second largest planet away from the Sun. | Unisex | English |
| Scooter | One who goes suddenly and speedily. | Unisex | English |
| Scout | Observer | Unisex | American English |
| Shark | | Unisex | Hebrew |
| Shasta | Name of a Native American tribe | Female | Native American |
| Sheba | Daughter of an oath | Female | Hebrew |
| Sherry | The plains | Female | Hebrew |
| Shiloh | Gift for him | Unisex | Hebrew |
| Shorty | Of less than average size | Unisex | English |
| Silver | Silver (the metal or colour) | Male | English |
| Skinny | | Unisex | Hebrew |