| remiss | Lacking care or attention to duty; negligent | |
| reminiscent | Tending to remind one of something | |
| remedial | Providing a remedy, curative; concerned with the correction of a problem | |
| relish | Great enjoyment | |
| relinquish | Voluntarily cease to keep or claim; give up | |
| rejuvenated | To make someone or something look or feel younger, fresher, or more lively | |
| refulgent | Shining very brightly | |
| refracted | Measuring the bending of a ray of light or sound wave when it enters a medium where its speed is different | |
| redundant | Not or no longer needed or useful; superfluous | |
| reductive | Tending to present a subject or problem in a simplified form, especially one viewed as crude. | |