| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| Siddhartha | - | Sanskrit, Bengali | ||
| Siddhi | - | Indian, Marathi | ||
| Sidonia | - | Late Roman, German | ||
| Sidonius | - | Late Roman | ||
| Siegbert | ZEEK-bert | German | ||
| Sieger | - | Dutch, German | ||
| Siegfried | ZEEK-freet (German) | German, Germanic Mythology | ||
| Sieghard | ZEEK-hahrt | German | ||
| Sieghild | - | German | ||
| Sieglinde | - | German, Germanic Mythology | ||
| Siegmund | ZEEK-muwnt | German | ||
| Siegward | - | German | ||
| Siemen | SEE-mən (Dutch) | Dutch, Frisian | ||
| Siet | SEET | Frisian | ||
| Sietse | SEET-sə | Frisian |