JCOS
| Acronym | Definition |
|---|---|
| JCOS | Joint Chiefs of Staff (Pentagon, USA; usually seen as JCS) |
| JCOS | Juneau Commission on Sustainability (Juneau, AK) |
| JCOS | Jefferson County Open School (Jefferson County, Colorado) |
| JCOS | Joint Countermine ACTD Simulation |
| JCOS | Joint Committee on Security (UK) |
| JCOS | Joint Countermine Operations Simulation |