| OCSA | Off Campus Student Association 
| Others |
| OCSA | Off Campus Students' Association
| Others |
| OCSA | Office of Controlled Substances Administration
| Others |
| OCSA | Office of Curricular and Student Affairs
| Others |
| OCSA | Office of the Chief of Staff, Army
| Others |
| OCSA | Ohio Construction Suppliers Association
| Others |
| OCSA | Olds College Students Association
| Others |
| OCSA | OnBase Certified System Administrator
| Others |
| OCSA | Onslow Classic Soccer Assn
| Others |
| OCSA | Onslow Classic Soccer Association
| Others |
| OCSA | Ontario Community Support Association
| Others |
| OCSA | Ontario Convenience Stores Association
| Others |
| OCSA | Oracle Cloud Startup Accelerator
| Others |
| OCSA | Orange County School of the Arts
| Others |
| OCSA | Orange County Sportsmen's Association
| Others |
| OCSA | Oregon Chimney Sweeps Association
| Others |
| OCSA | Organizational Communication Student Association
| Others |
| OCSA | Orthodox Christian Scout Association
| Others |
| OCSA | Osceola County School for the Arts
| Others |
| OCSA | Ouray County Soccer Association
| Others |
| OCSA | Ovarian Cancer Symptom Awareness
| Others |