| Radio | radio |
| radio- | radio- |
| Radiologe | radiologist |
| Radix | primitive |
| Rada | rada |
| Radiolarie | radiolarian |
| Radiotaste | radio button |
| Rad | wheel bicycle bike cartwheel rad |
| Radar | radar |
| Radau | racket |
| Radiologie | radiology |
| Radiologin | radiologist |
| Radiometer | radiometer |
| Radioröhre | thermionic valve |
| Radiosonde | radio altimeter |
| Radiowelle | radio wave radio station |
| Radium | radium |
| Radius | radius |
| Radom | radome |
| Radon | radon |