| Abbreviation | Definition |
|---|---|
| CMHPR | Center for Military Health Policy Research |
| CMHS | Canadian Military Heritage Society |
| CMI | Club Management Institute |
| CMLA | Commission for Motion Laboratory Accreditation, Inc. |
| CMOHS | Congressional Medal Of Honor Society |
| CMOU | Carolina Motorcycle Organizations United |
| CMPA | Canadian Medical Protective Association |
| CMR | Center for Military Readiness |
| CMS | Center for Medicare Services |
| CMT | Children's Musical Theatre |
| CMTA | Charcot Marie Tooth Association |
| CMTC | California Manufacturing and Technology Consulting |
| CN | Care Net |
| CNAAR | Center for North American Amphibians and Reptiles |
| CNAD | Center for a New American Dream |
| CNAG | Comunn NA G??idhlig (The Gaelic language Society) |
| CNAG | Comunn NA Gàidhlig (The Gaelic language Society) |
| CNAH | Center for North American Herpetology |
| CNCG | Clubul National de Ciobanesc German din Romania |
| CND | Campaign for Nuclear Disarmament |