| Sint-Amands | Sint-Amands |
| Sint-Andries | Sint-Andries |
| Sint-Genesius-Rode | Sint-Genesius-Rode |
| Sint-Gillis-Waas | Sint-Gillis-Waas |
| Sint-Katelijne-Waver | Sint-Katelijne-Waver |
| Sint-Laureins | Saint Lawrence River |
| Sint-Lievens-Houtem | Sint-Lievens-Houtem |
| Sint-Martens-Latem | Sint-Martens-Latem |
| Sint-Michiels | Sint-Michiels |
| Sint-Niklaas | Saint Nicholas |
| Sint-Pieters-Leeuw | Sint-Pieters-Leeuw |
| Sint-Truiden | Sint-Truiden |
| sintagma nominal | noun phrase |
| sintaxe | syntax |
| sintaxeha | syntaxds |
| sintetizador | synthesizer |
| sintetizador (eletrônico) | synthesizer |
| sintetizador(eletrônico) | synthsizer |
| sintetizar | synthesize |
| sinto muito | sorry |
| sintoma | symptom |
| sintomaha | symptoms |
| sintomas clínicos | clinical symptom |
| sintomatologia | semiotics |
| sintomático | symptomatic |
| sintoniaha | tuningds |
| sintonizador | tuner |
| sintonizar | tune in |
| Sintra | Sintra |
| sintático | syntactic |
| sintáticoa | syntactic |
| sintético | artificial |
| sintéticoa | synthetic |
| sintéticos | synthetics |
| sinuca | snooker |
| sinucaha | billiards |
| sinuosidade | sinuosity |
| sinuoso | sinuous |
| sinuosoha | winding |
| sinusite | sinusitis |
| Sinzheim | Sinzheim |
| sinédoque | synecdoche |
| Sinédrio | Sanhedrin |
| sinítico | Sinitic |
| sinólogo | sinologist |
| sinónimo | synonymous |
| sinônimo | synonymous |
| sinônimoha | synonymous |
| Siobhán Donaghy | Siobhán Donaghy |
| Sion | Zion |
| sionismo | Zionism |
| Sionismo trabalhista | Labor Zionism |
| sionismoha | Zionisme |
| sionista | Zionist |
| sionistaha | Zioniste |
| Sioux | Sioux |
| siouxha | Dakotae |
| Siouxsie Sioux | Siouxsie Sioux |
| Sipahi | Sipahi |
| sipaio | sepoy |
| Sipaliwini | Sipaliwini District |
| Sipalki | Shippalgi |
| Siphonophora | Siphonophora |
| Sippar | Sippar |
| Sipplingen | Sipplingen |
| Siptah | Siptah |
| Sipuncula | Sipuncula |
| sique | Sikh |
| Siquim | Sikkim |
| Sir | Sir |
| Sir Dária | Syr Darya |
| Sir Mix-A-Lot | Sir Mix-a-Lot |
| Sira | Sirah Rasul Allah |
| Siracusa | Syracuse |
| Siraitia | Siraitia grosvenorii |
| Sirdal | Sirdal |
| Siren intermedia | Lesser Siren |
| Siren lacertina | Greater Siren |
| sirene | siren |
| sirene de nevoeiro | foghorn |
| sireneha | sirene |
| Sirenia | Sirenia |
| Sirenidae | Siren |
| Siret | Siret River |
| siri | crab |
| Siri Cascudo | Krusty Krab |
| Siri-azul | Blue crab |
| Sirianos | Syrian |
| sirigaita | minx |
| Sirimavo Bandaranaike | Sirimavo Bandaranaike |
| Sirion | River Sirion |
| siririca (vulgar) | finger-fucking |
| Sirius | Sirius |
| Sirius Black | Sirius Black |
| Sirkap | Sirkap |
| Sirmione | Sirmione |
| Sirnach | Sirnach |
| siroco | sirocco |
| Siryn | Siryn |
| Sisak | Sisak |
| sisal | sisal |
| SISD | SISD |
| Sisenando | Sisenand |
| Sisikon | Sisikon |
| sismo | earthquake |
| Sismo interplacas | Interplate earthquake |
| sismografia | seismology |
