| Abbreviation | Definition |
|---|---|
| CMBA | Calgary Minor Basketball Association |
| CMBA | Classic Moth Boat Association |
| CMBC | Carmel Mountain Bike Club |
| CMC | Caravan Manoeuvring Championships |
| CMC | Card Master Conflict |
| CMC | Colorado Mountain Club |
| CMFL | Cambodian Midget Fighting League |
| CMGA | Canadian Mounted Games Association |
| CMHA | Cumberland Minor Hockey Association |
| CMK | Crabbet Maynesboro Kellogg |
| CMLA | Catholic Metro League of Atlanta |
| CMLL | Consejo Mundial de Lucha Libre |
| CMLW | Curly Maple Ultra Leather Wrap Custom Pool Cue |
| CMP | Carolina Motorsports Park |
| CMSA | Chicago Metropolitan Sports Association |
| CMSC | Chicago Metropolitan Ski Council |
| CMSC | Cleveland Metropolitan Ski Council |
| CMSTS | Colorado Mountain Soccer Tournament Series |
| CMT | Connor Michael Turner |
| CMT | Custom Maps Tournament |