| Acronym | Definition |
|---|
| OEC | Outdoor Emergency Care |
| OEC | Ocean Energy Council |
| OEC | Oxygen Evolving Complex (photosynthesis) |
| OEC | Otis Elevator Company |
| OEC | Ormat Energy Converter |
| OEC | Overseas Employment Corporation (Pakistan) |
| OEC | Operational Evaluation Command |
| OEC | Oxygen Equilibrium Curve |
| OEC | Other Exchange Company |
| OEC | overall evaluation criteria |
| OEC | Office of Evangelization and Catechesis |
| OEC | Outback Environmental Controls (Brisane, QLD, Australia) |
| OEC | Ocean Engineering Centre, Canada |
| OEC | Operations Engineering Center |
| OEC | Operations and Engineering Contractor |
| OEC | Organizational Effectiveness Evaluation Checklist (management tool) |
| OEC | Open Energy Corporation |
| OEC | Oregon Employer Council |
| OEC | Old Earth Creationism (belief system) |
| OEC | Olfactory Ensheathing Cell |
| OEC | Oil Exploration Company (Iraq) |
| OEC | Office of Exceptional Children (various locations) |
| OEC | Oil Exporting Country (economics) |
| OEC | Office of Environmental Coordination (New York, NY) |
| OEC | Ohio Expo Center (Columbus, OH) |
| OEC | Operational Employment Concept |
| OEC | Oklahoma Electric Cooperative, Inc. (Norman, OK) |
| OEC | Ontario Engineering Competition |
| OEC | Ohio Environmental Council |
| OEC | Office of Emergency Communications |
| OEC | Original Equipment Cost |
| OEC | On Every Corner (entertainment) |
| OEC | Ovarian Epithelial Cancer |