| Knotentheorie | knot theory |
| Quantentheorie | quantum theory |
| Mengentheorie | set theory |
| Dramentheorie | dramatic theory |
| Wellentheorie | wave model wave theory |
| Zahlentheorie | theory of numbers |
| Systemtheorie | system theory |
| Automatentheorie | automata theory |
| Graphentheorie | graph theory |
| Gruppentheorie | group theory |
| Pongidentheorie | Pongidae hypothesis |
| Spieltheorie | game theory |
| Koketterie | coquetry |
| knottern | complain |
| Notenrolle | piano roll |
| Notenwert | note value |
| Kastenheirat | endogamy |
| Dysenterie | dysentery |
| Kategorientheorie | category theory |
| Eichtheorie | gauge theory |