| Abbreviation | Definition |
|---|---|
| CIMVHR | Canadian Institute for Military and Veterans' Health Research |
| CIN | Cadet Information Number |
| CIN | Cargo Increment Number |
| CIN | Change Identification Number |
| CIN | Container Identification Number |
| CINC | Commander In Chief |
| CinC | Commander-in-Chief |
| CINCCENT | Commander IN Chief CENTral Command |
| CINCFOR | Commander IN Chief FORces Command |
| CINCNORAD | Commander-in-Chief North American Defense Command |
| CINCPAC | Commander IN Chief PACific |
| CINCSO | Commander IN Chief SOuthern Command |
| CINCUNC | Commander IN Chief United Nations Command |
| CINCUSAREUR | Commander IN Chief United States Army, EURope |
| CIO | Central Imagery Office |
| CIO | Central Intelligence Officer |
| CIO | Command Intelligence Officer |
| CIO | Coordination, Implementation, and Operation |
| CIOC | Counterinsurgency Operations Command |
| CIOTA | Counter-Intelligence Operational Tasking Authority |