| COSO | Central Operations Services Office 
| Others |
| COSO | Coalition On Sexual Orientation
| Others |
| COSO | Combat Oriented Supply Operations
| Others |
| COSO | Comittee of Sponsoring Organizations
| Others |
| COSO | Committee of Sponsoring Organisations
| Others |
| COSO | Committee Of Sponsoring Organizations
| Others |
| COSO | Committee of Sponsoring Organizations of the Treadway Commission
| Others |
| COSO | Committee of Supporting Organizations
| Others |
| COSO | Committee on Secure Organizations
| Others |
| COSO | Committee On Student Organizations
| Others |
| COSO | Consortium Of Somali Organisations
| Others |
| COSO | Council Of Student Organizations
| Others |
| COSO | Council On Sexual Orientation
| Others |
| COSO | Council On Student Organizations
| Others |