| Word | Description |
| OCHE | Office of Commissioner of Higher Education |
| OCLC | Online Computer Library Center |
| OERI | (federal) Office of Education Research and Information |
| ONDCP | Office of National Drug Control Policy |
| OPI | The Montana Office of Public Instruction |
| OPI or MOPI | Montana Office of Public Instruction, although OSEP refers to us more formally, as MOPI |
| OSEP | Office of Special Education Programs within the OSERS |
| OSERS | Office of Special Education and Rehabilitation Services of the Department of Education |
| OTO | One-Time-Only (OTO) Payment |
| OTT | Omicron Tau Theta (National Honorary Professional Graduate Society in Vocational Education) |
| OVAE | Office of Vocational and Adult Education |