| Synoptik | synoptic meteorology |
| Synopse | synopsis |
| synoptisch | synoptic synoptical |
| Optik | optics |
| Noetik | noetic |
| Synesis | constructio ad sensum |
| Synapse | synapse |
| Synergie | synergy |
| Synkope | syncope fainting |
| Synode | synod ecclesiastical council |
| Synonym | synonym convertible terms equivalent terms synonymous word |
| synonym | synonymous |
| Synonymie | synonymy |
| Syntax | syntax |
| Syntänie | synteny |
| kynophob | cynophobic |
| Gynoid | gynoid |
| Nynorsk | Nynorsk Neo-Norwegian New Norwegian |
| Anopie | anopia |
| Anopsie | anopia |