- Observer
- Observer newspaper
- Off-Campus Housing
- Office for the Protection of Research Subjects
- Office of Administration and Planning
- Office of Fellowships
- Office of Research Safety
- Office of Sponsored Research
- Office of Strategic Initiatives
- Office of the President
- Office of the Provost
- Office of the University Chaplain
- Office Supply Stores (University Services)
- Office Systems Equipment (University Services)
- Olympics, Special
- One Love
- Optimization Technology Center
- Organized Assistance by Students Investing in Service
(OASIS) - Orthotic Center, Rehabilitation Engineering and Prosthetic
and - Outing Club
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