| Abbreviation | Definition |
|---|---|
| RDN | Rational Developer Network |
| RDN | Relative Distinguished Name |
| RDO | Raster Data Object |
| RDO | Referenced Data Object |
| RDRAM | Rambus Dynamic Random Access Memory |
| RDS | Relational Data System |
| RDT | Rapid Deployment Template |
| RE | Regular Expression |
| READY | Real-time Environmental Applications and Display sYstem |
| REBOOT | Re-Use Based Object Oriented Technology |
| REL | Release |
| REO | Responsible Engagement Overlay |
| REP | Read, Evaluate, Print |
| REP | Remotely Executable Program |
| RES | Restore |
| RESP | Registered Education Savings Plan |
| RET | RETurn |
| REW | Rewind |
| REZ | Resolution |
| RF | Resume Flag |