| 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 |