| Acronym | Definition |
|---|
| COSA | Committee on Substance Abuse (various organizations) |
| COSA | City of San Antonio (Texas) |
| COSA | Court of Special Appeals (Maryland) |
| COSA | City of Saint Augustine (Florida) |
| COSA | Council of State Archivists |
| COSA | Circles of Support and Accountability |
| COSA | Collegiate Society of Advertising (Ateneo de Manila University; Philippines) |
| COSA | Codependents of Sex Addicts |
| COSA | Committee on Sustainability Assessment (international consortium) |
| COSA | Certificates of On-Site Systems Approval (confirmation of septic system inspection) |
| COSA | Cost-of-Service Analysis |
| COSA | Co-Sex Addicts Anonymous (Minneapolis, MN) |
| COSA | City of Santa Ana (California) |
| COSA | Carbon Monoxide Safety Association (Eastlake, CO) |
| COSA | Coordinator of Student Activities |
| COSA | Casualties of Sexual Allegations |
| COSA | Company of Science & Art |
| COSA | Clustering Objects on Subsets of Attributes |
| COSA | Children of Substance Abuse |
| COSA | Communications Open System Architecture |
| COSA | Central Ontario Soaring Association |
| COSA | Combat Operational Support Aircraft |
| COSA | Corps Service Area |
| COSA | Coptic Orphans Support Association (Falls Church, VA) |
| COSA | Computational Social Aggregation |