| Acronym | Definition |
|---|
| REL | Religion |
| REL | Reliability |
| REL | Relative |
| REL | Relief |
| REL | Relation |
| REL | Relieved |
| REL | Regional Educational Laboratory |
| REL | Relocate |
| REL | Real Estate Law |
| REL | Renewable Energy Law (various locations) |
| REL | Releasable |
| REL | Recommended Exposure Limit (NIOSH) |
| REL | Remaining Economic Life (real estate) |
| REL | Radio Emscher Lippe (German online radio) |
| REL | Relações Internacionais (Brazil) |
| REL | Redhat Enterprise Linux |
| REL | Release |
| REL | Relayer |
| REL | Rights Expression Language |
| REL | Ressources Educatives Libres (French: Open Educational Resources) |
| REL | Reliance Energy Ltd |
| REL | Release/Released |
| REL | Release Message |
| REL | Reference Exposure Level |
| REL | Rear End Loader (waste container) |
| REL | V-Rel Avian Reticuloendotheliosis Viral Oncogene Homolog |
| REL | Radio Equipment List (Canada) |
| REL | Trelew, Chubut, Argentina (Airport Code) |
| REL | Réticulum Endoplasmique Lisse (French: Smooth Endoplasmic Reticulum) |
| REL | Authorized for Release To ... |
| REL | Rassemblement Européen de la Liberté (French: European Gathering of Liberty; political platform) |
| REL | Réacteur à Eau Légère (French: Light Water Reactor) |
| REL | Recovered Energy Logic |
| REL | Random Even Lengths (lumber) |
| REL | Ring Enhancing Lesion |
| REL | Richland Energy Laboratory (Tri-Cities University Center) |