| Name | Meaning | Gender | Origin |
|---|
| Reese | Enthusiasm | Male | Welsh |
| Rizzo | | Unisex | Hebrew |
| Rocco | Battle cry | Male | Germanic |
| Romeo | Pilgrim to Rome | Male | Italian |
| Ronnie | Ruler with counsel | Unisex | Norse |
| Rose | Rose | Female | Latin |
| Rowdy | Boisterous. Western Nickname. | Unisex | English |
| Rusty | Rusty, full of rust | Unisex | American English |
| Sabrina | A Welsh river name | Female | Gaelic |
| Sassy | Lively and spirited | Unisex | English |
| Sawyer | One who saws wood | Male | English |
| Scooby | | Unisex | Hebrew |
| Scooter | One who goes suddenly and speedily. | Unisex | English |
| Scout | Observer | Unisex | American English |
| Serena | Composed | Female | Latin |
| Smoky | | Unisex | Hebrew |
| Socks | Short stockings finishing above the ankle | Unisex | English |
| Spartacus | From the city of Sparta | Unisex | English |
| Spencer | Someone who gives out goods | Male | French |
| Spike | A long, thick sharp-pointed piece of wood or metal | Male | English |
| Splinter | | Unisex | Hebrew |
| Sprint | | Unisex | Hebrew |
| Spunky | Spirited, plucky. | Unisex | English |
| Star | Star | Female | Latin |
| Stuart | Gaurdian of the House | Male | English |
| Sugar | A sweet powder from sugar cane. Slang for sweetheart. | Female | English |
| Suzie | Lily | Unisex | Hebrew |
| Sylvia | Wooded | Female | Latin |
| Talia | Dew of God | Female | Hebrew |
| Tammy | Twin | Female | Aramaic |