| K.-o.-System | knockout system |
| IT-System | IT system |
| Exosystem | exosystem |
| Tonsystem | pitch space |
| Ökosystem | ecosystem |
| Larsen-System | Larsen's Opening Queen's Fianchetto Opening |
| Dateisystem | file system |
| Justizsystem | judiciary |
| Notensystem | stave |
| Soundsystem | sound system |
| Typsystem | type system |
| Untersystem | sub-system |
| Wahlsystem | voting system |
| Zehnersystem | decimal |
| Abgassystem | exhaust gas system exhaust system |
| Agroökosystem | agroecosystem agrosystem |
| Bezugssystem | frame of reference reference frame |
| Binärsystem | binary system |
| Immunsystem | immune system |
| Leitsystem | distributed control system |