| Sigdal | Sigdal |
| Sigeberht del Wessex | Sigeberht of Wessex |
| Sigeberto I | Sigebert I |
| Sigeberto II | Sigebert II |
| Sigeberto III | Sigebert III |
| Sigerico | Sigeric |
| Sigfrido | Siegfried |
| siggillare | seal |
| Sighetu Marmaţiei | Sighetu Marmaţiei |
| Sighişoara | Sighişoara |
| Sigieri da Brabante | Siger of Brabant |
| sigillante | sealant |
| sigillare | seal |
| sigillo | seal |
| Sigillo LMLK | LMLK seal |
| SIGINT | SIGINT |
| Sigirino | Sigirino |
| Sigiriya | Sigiriya |
| Sigismondo | Sigismund of Burgundy |
| Sigismondo di Svezia | Sigismund III Vasa |
| Sigismondo I di Polonia | Sigismund I the Old |
| Sigismondo II Augusto di Polonia | Sigismund II Augustus |
| Sigismondo Pandolfo Malatesta | Sigismondo Malatesta |
| Sigismund Thalberg | Sigismond Thalberg |
| Sigismund von Herberstein | Sigismund von Herberstein |
| Sigla automobilistica internazionale | List of international license plate codes |
| sigla musicale | signature tune |
| siglare | initial |
| Sigle automobilistiche italiane | Italian car number plates |
| Sigle degli ordini religiosi cattolici | Catholic order |
| Sigle delle congregazioni benedettine | Benedictine Confederation |
| Sigleß | Sigleß |
| Siglistorf | Siglistorf |
| Siglo de oro | Spanish Golden Age |
| Sigma | Sigma |
| Sigma Draconis | Sigma Draconis |
| Sigma Octantis | Sigma Octantis |
| Sigma Olomouc | SK Sigma Olomouc |
| Sigma-algebra | Sigma-algebra |
| Sigmar Heldenhammer | Sigmar |
| Sigmaringen | Sigmaringen |
| Sigmaringendorf | Sigmaringendorf |
| Sigmarszell | Sigmarszell |
| Sigmatismo | Lisp |
| Sigmund Freud | Sigmund Freud |
| Sigmund Jähn | Sigmund Jähn |
| Sigmundsherberg | Sigmundsherberg |
| Sign of the Hammer | Sign of the Hammer |
| Signac | Signac |
| Signal de Botrange | Signal de Botrange |
| Signal Iduna Park | Signal Iduna Park |
| Signal recognition particle | Signal recognition particle |
| Signature | Signature |
| Signau | Signau |
| significanza | significance |
| significare | mean |
| significativamente | significantly |
| significatività | significance |
| significativo | significant |
| significato | sense |
