| Abbreviation | Definition |
|---|---|
| JAS | Jrok's Arcade Simulator |
| JAS | Jumping And Style (Showjumping Competition) |
| JAT | Junior Advanced Team |
| JAVA | Japanese American Volleyball Association |
| JAZ | Judoclub Atus Zeltweg |
| JBSC | Jensen Beach Soccer Club |
| JBT | Junior Bowlers Tour |
| JBW | Johns Backyard Wrestling |
| JC | Junior Courser |
| JC | Junior Cycle |
| JCCC | Jacques-Cartier Curling Club |
| JCRA | Junction City Rodeo Association |
| JCRP | Johnny Cake Ridge Park |
| JCS | Jockey Club Student |
| JCSA | Jefferson County Sports Association |
| JCSA | Jersey Coast Shark Anglers |
| JCSA | Josephine County Sportsman's Association |
| JCSC | Jefferson City Swim Club |
| JCSF | Jersey Coast Sport Fliers |
| JCSQ | Jockey Club Student Quarters |