| OEC | Elite CFD 
| Others |
| OEC | Oakland Early College
| Others |
| OEC | Observatory of Economic Complexity
| Others |
| OEC | Ocean Energy Council
| Others |
| OEC | Ocussi, Indonesia
| Others |
| OEC | Odd Engineering Contraption
| Others |
| OEC | Office Environment Company
| Others |
| OEC | Office Equipment Company of Mobile
| Others |
| OEC | Office of Early Childhood
| Others |
| OEC | Office of Emergency Communications
| Others |
| OEC | Office of Environmental Coordination
| Others |
| OEC | Offshore Engineered Component
| Others |
| OEC | Offshore Engineered Components
| Others |
| OEC | Ohio Empowerment Coalition
| Others |
| OEC | Ohio Environmental Council
| Others |
| OEC | Oil Exploration Company
| Others |
| OEC | Oklahoma Electric Cooperative
| Others |
| OEC | Old Earth Creation
| Others |
| OEC | Old Earth Creationism
| Others |
| OEC | Old Ellicott City
| Others |
| OEC | Olfactory Ensheathing Cells
| Others |
| OEC | Olfactory Ensheating Cell
| Others |
| OEC | Oman e-Commerce Conference
| Others |
| OEC | Online Education Courses
| Others |
| OEC | Online Ethics Center
| Others |
| OEC | Only Envying Clowns
| Others |
| OEC | Ontario Engineering Competition
| Others |
| OEC | Open Education Consortium
| Others |
| OEC | Open Ended Contract
| Others |
| OEC | Open Enterprise Computing
| Others |
| OEC | Operational Evaluation Command
| Others |
| OEC | Opportunties in Emergency Care
| Others |
| OEC | Optic Edge Corporation
| Others |
| OEC | Opus Embedded Command
| Others |
| OEC | Oracle Engagement Cloud
| Others |
| OEC | Orange Empire Conference
| Others |
| OEC | Orbital Engine Corporation
| Others |
| OEC | Ordinem Eccentrici Coctores
| Others |
| OEC | Ordinem Ecentrici Coctores
| Others |
| OEC | Ordre des Experts Comptables (France)
| Others |
| OEC | Oregon Employer Council
| Others |
| OEC | Oregon Environmental Council
| Others |
| OEC | Oregon Evidence Code
| Others |
| OEC | Organization Executive Course
| Others |
| OEC | Original Equipment Cost
| Others |
| OEC | Orion Engineered Carbons
| Others |
| OEC | Osborne Engineering Company
| Others |
| OEC | Osbourne Engineering Company
| Others |
| OEC | Otis Elevator Company
| Others |
| OEC | Ouachita Enterprise Community
| Others |
| OEC | Outdoor Education Center
| Others |
| OEC | Outdoor Emergency Care
| Others |
| OEC | Output Edge Control
| Others |
| OEC | Overall Evaluation Criterion
| Others |
| OEC | Overly Excessive Crap
| Others |
| OEC | Overseas Employment Certificate
| Others |
| OEC | Overseas Employment Corporation
| Others |
| OEC | Oxygen Equilibrium Curve
| Others |
| OEC | Oxygen Evolution Catalyst
| Others |
| OEC | Oxygen Evolving Complex
| Others |
| OEC | Oxygen-Evolving System
| Others |
| OEC | The Order Of Eternal Champions
| Others |