| Abbreviation | Definition |
|---|---|
| RES | Reservation Economic Summit |
| RETC | Rapid Excavation and Tunneling Conference |
| RETC | Rapid Excavation Tunneling Conference |
| RHF | Reproductive Health Forum |
| RIBC | Regional Ismaili Business Conference |
| RIC | Regulatory Information Conference |
| RICAP | Roma International Conference on Astroparticle Physics |
| RICC | Robotics Innovations Competition and Conference |
| RIDE | International Workshop on Research Issues on Data Engineering |
| RIGC | Romanian International Gas Conference |
| RISP | IEEE Computer Society Symposium on Research In Security and Privacy |
| RISS | RtI for International Schools Summit |
| RITC | Region IX Interpreter Training Consortium |
| RITS | Remediation Innovative Technology Seminar |
| RJC | Researchers' & Journalists' Conference of Japan |
| RL | Right Location |
| RLC | Redefining Learning Conference |
| RLC | Regional Leadership Conference |
| RLC | Republican Leadership Conference |
| RLC | Restaurant Leadership Conference |