| Abbreviation | Definition |
|---|---|
| OCSI | Oxford and Cambridge Society of India |
| OCTAA | On Campus Talking About Alcohol (alcohol education program; various universities) |
| OCU | Oakland City University |
| OCU | Ohio Christian University |
| OCU | Oklahoma City University |
| OCU | Oklahoma City University's |
| OCUA | Ontario Council on University Affairs |
| OCUA | Ottawa Carleton Ultimate Association |
| OCUR | Ontario Council on University Research |
| OD | Outgoing Degree |
| OD | Outside Discussions |
| OD | Oxford Dictionary |
| ODA | Office of Disability Accommodation |
| ODAA | Office of Diversity and Affirmative Action |
| ODC | Ocean Discovery Center |
| ODCE | Open Distributed Computing Environments (University of Helsinki; Finland) |
| ODT | Optical Detector Team |
| ODTU | Orta Dogu Teknik Üniversitesi |
| ODTU | Orta Doğu Teknik Üniversitesi |
| ODTU | Orta Do u Teknik Üniversitesi |