| SignÝ | | - | Ancient Scandinavian, Norse Mythology, Icelandic | |
| SigrÍ&Eth;R | | - | Ancient Scandinavian | |
| SigrÚN | | - | Ancient Scandinavian, Norse Mythology, Icelandic | |
| Sigsteinn | | - | Ancient Scandinavian | |
| Sigur&Eth;R | | - | Ancient Scandinavian, Norse Mythology | |
| Silvanus | | sil-VAY-nəs (English) | Roman Mythology, Ancient Roman, Biblical, Biblical Latin | |
| Simonides | | - | Ancient Greek | |
| Sindri | | - | Norse Mythology, Ancient Scandinavian, Icelandic | |
| Siward | | - | Ancient Germanic | |
| SluaghadhÁN | | - | Ancient Irish | |
| Snorri | | - | Ancient Scandinavian, Icelandic | |
| Socrates | | SAHK-rə-teez (English) | Ancient Greek (Latinized) | |
| Sokrates | | - | Ancient Greek | |
| Solon | | - | Ancient Greek | |
| Somarli&Eth;R | | - | Ancient Scandinavian | |