| Abbreviation | Definition |
|---|---|
| OASIS | Online Administrative Student Information System |
| OASIS | Online Advising Student Information System |
| OASR | Office of Advocacy Student Representation |
| OATS | Open Access to Textbooks for Students |
| OBIC | Our Bond Is Closest |
| OBS | Organization of Bengali Students |
| OBSS | Office of Black Student Services |
| OCDC | Oberlin College Dialogue Center |
| OCP | Overseas Community Project |
| OCSA | Off Campus Student Association |
| OCSA | Off Campus Students' Association |
| OCSA | Olds College Students Association |
| OCSG | Overleg Christelijke Studentenverenigingen Groningen |
| ODE | Omicron Delta Epsilon |
| ODK | Omicron Delta Kappa |
| ODOS | Office of the Dean Of Students |
| ODSD | Office of the Dean for Student Development |
| OFS | Office For Students |
| OFSS | Online Facilitation System for Students |
| OG | Oxford Graduate |