| Acronym | Definition |
|---|
| OPAC | Online Public Access Catalog |
| OPAC | Online Public Access Catalogue |
| OPAC | Office of Public Affairs and Communications (various schools) |
| OPAC | Operations, Planning, Accounting and Control (Eindhoven University of Technology; Netherlands) |
| OPAC | Outside Plant Access Cabinet (telecommunications) |
| OPAC | Ontario Property Assessment Corporation |
| OPAC | Online Payment and Collection |
| OPAC | Office Proficiency Assessment& Certification |
| OPAC | Orlando Performing Arts Center (Florida, USA) |
| OPAC | Olympic Peninsula Arabian Club (horses) |
| OPAC | Older Persons Action Centre (Australia) |
| OPAC | Office of Procurement and Contracts |
| OPAC | Office Proficiency and Assessment Certification |
| OPAC | Optimization Policies for Adaptive Control (Computer Strategy for Adative Control of Traffic Signals) |
| OPAC | Overall Performance Appraisal Certification |
| OPAC | Oficina de Planificación y Articulación Curricular |