| RLN | recurrent laryngeal nerve; regional lymph node; relaxin |
|---|---|
| ROU | recurrent oral ulcer |
| RPE | rate of perceived exertion; recurrent pulmonary embolism; retinal pigment epithelium; ribulose 5-pho... |
| RRI | recurrent respiratory infection; reflex relaxation index; relative response index |
| RRIS | recurrent respiratory infection syndrome |