| Acronym | Definition |
|---|
| OspA | Outer Surface Protein A |
| OspA | Office of Sponsored Projects Administration |
| OspA | Orquestra Sinfônica de Porto Alegre (Porto Alegre, Brazil) |
| OspA | Oregon State Pharmacy Association (est. 1889) |
| OspA | Oregon School Personnel Association |
| OspA | Oxygenated Solvent Producers Association |
| OspA | Open Services Partner Alliance (Avant Telecom, Inovative Systems, Nextone, Sonus) |
| OspA | Ohio School Psychologists Association |
| OspA | Oregon School Psychologists Association |
| OspA | Oklahoma School Psychological Association |
| OspA | Operator Service Providers of America |
| OspA | Oregon State Poets Association |
| OspA | Operations Security Professionals Association |
| OspA | Office of Systems Product Assurance |