| Acronym | Definition |
|---|
| COSAC | Conférence des Organes Spécialisés dans les Affaires Communautaires (French: Conference of Community and European Affairs Committees of the Parliaments of the European Union) |
| COSAC | Center for Outreach and Services for the Autism Community |
| COSAC | Cometary Sampling and Composition (experiment) |
| COSAC | Conferenza degli Organismi Specializzati Negli Affari Comunitari ed Europei dei Parlamenti dell'Unione Europea (Italian: Conference of Community and European Affairs Committees of the Parliaments of the European Union) |
| COSAC | Canadian Open Systems Applications Criteria |
| COSAC | Coalition of Service and Charity (Foundation; Florida) |
| COSAC | Church of Service and Charity (Hollywood, Florida) |
| COSAC | Charity of Sean Anthony Cononie (Hollywood, Florida a group of service agencies) |