| Snezhana Goryanova |
4 |
| Snezhana Veleva |
1 |
| snow fridge |
1 |
| soapstone (steatite) |
2 |
| Sochi |
1 |
| social media |
1 |
| Social Sciences and Humanities Research Council of Canada |
1 |
| Socialist Republic of Romania |
2 |
| Södertörn University |
4 |
| Soenke Dangendorf |
1 |
| Sofia |
99 |
| Sofia - Kardam Train Fire |
1 |
| Sofia - Vidin Highway |
1 |
| Sofia Airport |
1 |
| Sofia amphitheater |
1 |
| Sofia Appellate Court |
1 |
| Sofia City Prosecutor's Office |
4 |
| Sofia Holy Mountain |
1 |
| Sofia Hyatt Hotel |
1 |
| Sofia International Airport |
6 |
| Sofia Largo |
28 |
| Sofia Mayor |
17 |
| Sofia Metropolitan |
2 |
| Sofia Metropolitan's Office |
1 |
| Sofia Municipality |
43 |
| Sofia Regional Museum of History |
8 |
| Sofia Ring Road |
7 |
| Sofia Sanjak |
2 |
| Sofia University "St. Kliment Ohridski" |
28 |
| Sofia University Library |
1 |
| Sofia Valley |
3 |
| Sofiya Hristeva |
5 |
| Sofiya Hristova |
2 |
| solidi |
1 |
| solidus |
7 |
| Solon |
1 |
| Somerset County |
1 |
| sonar |
1 |
| Sonderborg |
1 |
| Song of Ice and Fire |
3 |
| Sonya Lazarova |
1 |
| Sonya Semerdzhieva |
1 |
| Sophocles |
1 |
| Sopot |
4 |
| Sorbonne |
1 |
| Sostra Fortress |
7 |
| Sotir Ivanov |
7 |
| Sotir Tsatsarov |
5 |
| Sotiris Simeonidis |
4 |
| South Africa |
2 |
| South America |
3 |
| South Korea |
2 |
| South Tower Museum |
1 |
| Southeast Bulgaria |
31 |
| Southeast Europe |
3 |
| Southern Dobrudzha |
3 |
| Southern Germany |
1 |
| Southern Italy |
2 |
| Southwest Bulgaria |
17 |
| Southwestern Bulgaria |
26 |
| Southwestern University "Neofit Rilski" |
2 |
| Southwestn Gate of Odessos |
1 |
| Soviet Bloc |
2 |
| Soviet Union |
23 |
| Sozopol |
77 |
| Sozopol Fotress |
1 |
| Sozopol Mayor |
7 |
| Sozopol Municipality |
17 |
| Sozopol Museum of Archaeology |
7 |
| Sozopol Vampire |
2 |
| Sozopolis |
6 |
| spa center |
2 |
| spa resort |
24 |
| space ship |
3 |
| space shuttle |
3 |
| space suit |
1 |
| Spain |
15 |
| Spanish Colonial Empire |
1 |
| Sparta |
1 |
| Spartacus |
2 |
| Spartak Nikolov |
1 |
| Spas Mashov |
2 |
| spatha |
5 |
| spear |
7 |
| spear tip |
11 |
| Specialized Experts’ Council for Preservation of Cultural Properties |
1 |
| Specialized Prosecutor's Office |
4 |
| speleologist |
3 |
| speleology |
2 |
| speleothems |
1 |
| spelt |
1 |
| spelt (dinkel wheat or hulled wheat |
2 |
| Sphinx |
2 |
| sphragistics |
1 |
| spies |
1 |
| spindle |
1 |
| spindle whorl |
5 |
| spiral |
3 |
| spiral staircase |
1 |
| SPLASHCOS |
4 |
