| Abbreviation | Definition |
|---|---|
| CMAC | Costa Mesa Aquatics Club |
| CMAC | Crystal Mountain Alpine Club |
| CMAE | Club Milanese AutoMotoveicoli d'Epoca |
| CMBC | Canterbury Mountain Bike Club |
| CMBC | Casper Mountain Biathlon Club |
| CMBC | Center Mall Bridge Club |
| CMBC | Colwick Marina Boat Club |
| CMC | Carolina Mountain Club |
| CMC | Chicaco Mountaineering Club |
| CMC | Continental Motosport Club |
| CMCB | Classic Motor Club del Bages |
| CME | Club Music Elements |
| CMGB | Club Medical du Grand Boulogne |
| CMLC | Cheyenne Mountain Lacrosse Club |
| CMNB | Club Maitres Nageurs Beauport |
| CMOC | Counties Manukau Orienteering Club |
| CMPO | Club de Mar Port Ol??mpic |
| CMPO | Club de Mar Port Olímpic |
| CMRC | Canadian Motorsport Racing Club |
| CMRC | Central Minnesota Retriever Club |