| C2 | Command and control |
| CA | Civil affairs; Combat assessment; Coordinating altitude |
| CAAF | Contractors authorized to accompany the force |
| CAL | Critical asset list |
| CAO | Civil affairs operations |
| CAP | Civil augmentation program; Combat air patrol |
| CAS | Close air support |
| CASEVAC | Casualty evacuation |
| CATF | Commander, amphibious task force |
| CbT | Combating terrorism |
| CC | Critical capability |
| CCAS | Contingency contract administration services |
| CCDR | Combatant commander |
| CCIR | Commander’s critical information requirement |
| CCMD | Combatant command |
| CCO | Central control officer; Container control officer |
| CCS | Commander’s communication synchronization |
| CD | Counterdrug; Customer direct |
| CEM | Collected exploitable material |
| CFL | Coordinated fire line |
| CHE | Container-handling equipment |
| CI | Counterintelligence |
| CID | Combat identification |
| C-IED | Counter-improvised explosive device |
| CIM | Civil information management |
| CIP | Common intelligence picture |
| CJCSI | Chairman of the Joint Chiefs of Staff instruction |
| CJCSM | Chairman of the Joint Chiefs of Staff manual |
| CL | Contingency location; Coordination level |
| CLF | Commander, landing force |
| CLPSB | Combatant commander logistics procurement support board |
| CM | Collection manager; Cruise missile |
| CMO | Civil-military operations |
| CMOC | Civil-military operations center |
| CO | Cyberspace operations |
| COA | Course of action |
| COCOM | Combatant command |
| COG | Center of gravity |
| COIN | Counterinsurgency |
| COLPRO | Collective protection |
| COM | Chief of mission; Collection operations management |
| COMCAM | Combat camera |
| COMINT | Communications intelligence |
| COMSEC | Communications security |
| CONOPS | Concept of operations |
| CONPLAN | Concept plan; Contingency plan |
| CONUS | Continental United States |
| COOP | Continuity of operations |
| COP | Common operational picture |
| COR | Contracting officer’s representative |
| COS | Chief of staff |
| COSC | Combat and operational stress control |
| CP | Contact point; Control point |
| CR | Civil reconnaissance; Collection requirement; Critical requirement |
| CRA | Coordinating review authority |
| CRAF | Civil Reserve Air Fleet |
| CRM | Collection requirements management |
| CSA | Combat support agency |
| CSAR | Combat search and rescue |
| CSG | Carrier strike group |
| CSL | Cooperative security location |
| CSS | Combat service support |
| CSSA | Combat service support area |
| CT | Counterterrorism; Country team |
| CTE | Critical target element |
| CTF | Counter threat finance |
| CTL | Candidate target list |
| CTN | Countering threat networks |
| CTP | Common tactical picture |
| CUL | Common-user logistics |
| CV | Critical vulnerability |
| CVN | Aircraft carrier |
| CVW | Carrier air wing |
| CWC | Composite warfare commander |
| CWMD | Countering weapons of mass destruction |
| CWT | Customer wait time |