| SWR | Südwestrundfunk |
| SWT | Standard Widget Toolkit |
| swój | his |
| swędzenie | tingle |
| Sy | Sun Country Airlines |
| Syagriusz | Syagrius |
| Sybaris | Sybaris |
| sybaryta | Sybarite |
| Syberia | Siberia |
| Syberyjski Okręg Federalny | Siberian Federal District |
| Sybilla | Sibyl |
| Sybilla Jerozolimska | Sibylla of Jerusalem |
| Sybilla Koburg | Princess Sibylla of Saxe-Coburg and Gotha |
| Sybille Bammer | Sybille Bammer |
| Sybin | Sibiu |
| Sybir Nowosybirsk | HC Sibir Novosibirsk |
| SYBR Green | SYBR Green |
| Sychem | Shechem |
| Sycylia | Sicily |
| Sycylijczyk | sicilian |
| Sycylijska Wikipedia | Sicilian Wikipedia |
| sycylijski | Sicilian |
| Syczek | European Scops Owl |
| syczeć | hiss |
| Syczuan | Sichuan |
| Syców | Syców |
| Syd Barrett | Syd Barrett |
| Syddanmark | Region Syddanmark |
| Sydney | Sydney |
| Sydney Brenner | Sydney Brenner |
| Sydney Pollack | Sydney Pollack |
| Sydney Smith | Sydney Smith |
| Sydon | Sidon |
| Sydoniusz Apolinary | Sidonius Apollinaris |
| Syens | Syens |
| syf | jumble |
| syfilis | syphilis |
| Sygnalizacja kabinowa | Cab signalling |
| Sygnalizacja na LGV | LGV signalling |
| sygnalizacja świetlna | traffic light |
| sygnalizator | signalman |
| sygnał | signal |
| sygnować | sign |
| Sygryda Storråda | Sigrid the Haughty |
| Sygurd Fafnesbane | Sigurd |
| Syjam | Thailand |
| Syjamotyran | Siamotyrannus |
| Syjamski | Siamese |
| Syjon | Zion |
| syjonistyczny | Zionistic |
| syjonizm | Zionism |
| syk | hiss |
| sykatywa | dryer |
| Sykion | Sicyon |
| Sykkylven | Sykkylven |
| Sykoraks | Sycorax |
| Sykstus I | Pope Sixtus I |
| Sykstus II | Pope Sixtus II |
| Sykstus III | Pope Sixtus III |
| Sykstus IV | Pope Sixtus IV |
| Syktywkar | Syktyvkar |
| sylaba | syllable |
| sylabariusz | syllabary |
| Sylabariusz czirokeski | Cherokee syllabary |
| Sylabariusz kanadyjski | Canadian Aboriginal Syllabics |
| Sylabizm | Syllabic verse |
| Sylagusowate | Sillaginidae |
| Sylas | Silas |
| sylf | sylph |
| sylfida | sylph |
| Sylfion | Silphium |
| Syllable | Syllable |
| Syllabus Errorum | Syllabus of Errors |
