| rationell | economic |
| Rationale | rationale |
| irrationell | irrational |
| rational | rational |
| Ration | ration |
| arational | arational |
| national | national |
| redaktionell | editorial |
| traditionell | traditional |
| Radiowelle | radio wave radio station |
| Oration | collect |
| generationell | generational |
| Rating | rating |
| Ratio | reason ratio |
| Rätien | Raetia |
| Rätin | councillor councillour councilor councilour |
| Rätsel | riddle puzzle enigma mystery |
| irrational | irrational |
| rationieren | ration |
| -ation | -ation |