| Abbreviation | Definition |
|---|---|
| OPL | Open Part Library |
| OPL | Open Parts Library |
| OPL | Ossining Public Library |
| OPL | Ottawa Public Library |
| OPLA | Ontario Public Library Association |
| OPLD | Oakwood Public Library District |
| OPLD | Ontario Public Library Directory |
| OPLF | Orange Public Library Foundation |
| OPLF | Ottawa Public Library Foundation |
| OPLG | Ontario Public Library Guidelines |
| OPLIN | Ohio Public Library Information Network |
| OPLW | Ontario Public Library Week |
| OPPL | Oak Park Public Library |
| OPPL | Oak Park Public Library's |
| OPPL | Orland Park Public Library |
| OPPL | Ouachita Parish Public Library |
| ORCID | Open Researcher and Contributor ID |
| ORL | Okanagan Regional Library |
| ORLO | Oxford Rheumatology Library Online |
| ORLS | Ocmulgee Regional Library System |