| Abbreviation | Definition |
|---|---|
| RKO | Radio-Keith-Orpheum Radio Pictures Inc. |
| RKP | Registered Key Phrase |
| RKQ | Road Kill Quarterly |
| RKS | Romanized Korean Spelling |
| RKW | Registered Key Word |
| RL | Radio Liberty |
| RL | Real Live |
| RLA | Real Life Adventures |
| RLB | Radiant Light Broadcasting |
| RLE | Red Letter Edition |
| RLI | Radio Lakay International |
| RLL | Radio Liban Libre |
| RLM | Resource Library Magazine |
| RLMFI | relative linear median fluorescence intensity |
| RLT | Road Less Traveled |
| RMAR | Retail Mediation Activities Return |
| RMN | Radio Mindanao Network |
| RMN | Rocky Mountain News |
| RMN | Rumor Mill News |
| RMN | Rural Migration News |