| Acronym | Definition |
|---|
| REN | Ringer Equivalence Number |
| REN | Rename |
| REN | Rensselaer (Amtrak station code; Rensselaer, IN) |
| REN | Rede Eléctrica Nacional (Portugal) |
| REN | Orenburg (Russia) |
| REN | Requirements Engineering |
| REN | Rendering |
| REN | Ringer Equipment Number |
| REN | Remote Enable |
| REN | Resident Evil Network (gaming community website) |
| REN | Research and Educational Network |
| REN | Reef Education Network |
| REN | Resident Evil Nemesis (Playstation game) |
| REN | Research Exchange Network (various organizations) |
| REN | Restoration Ecology Network |
| REN | Rede Ecológica Nacional (Portugal) |
| REN | Real-Time Event Notification (PeopleSoft) |
| REN | Star Trek: Renaissance (fan fiction series) |
| REN | Radio Entertainment Network |
| REN | Regional Eye Network (TV show) |
| REN | Acadian Redfish |
| REN | Réseau Environnement Normandie (French: Normandy Environment Network; est. 1995) |
| REN | Radio en Nord (French Internet radio station) |