JCOS

AcronymDefinition
JCOSJoint Chiefs of Staff (Pentagon, USA; usually seen as JCS)
JCOSJefferson County Open School (Jefferson County, Colorado)
JCOSJoint Countermine ACTD Simulation
JCOSJoint Countermine Operations Simulation
JCOSJoint Committee on Security (UK)
JCOSJuneau Commission on Sustainability (Juneau, AK)