| Abbreviation | Definition |
|---|---|
| IM | Individual Medley |
| IM | Iron Man |
| IMAC | International Miniature Acrobatic Club |
| IMAO | Independent Martial Arts Organisation |
| IMAO | International Martial Arts Organization |
| IMBA | IMBAlanced |
| IMBA | International Mini Bike Association |
| IMBA | International Mountain Bicycling Association |
| IMBA | International Mountain Bike Association |
| IMBC | Irish Mountain Bike Club |
| IMBL | International Mixed Bowling League |
| IMC | Indy Media Center |
| IMC | International Multi-Cache |
| IMEN | International Men Enjoying Naturism |
| IMG | International Mountain Guides |
| IMGA | International Mounted Games Association |
| IMHA | Ilderton Minor Hockey Association |
| IML | International Marching League |
| IMP | International Match Point |
| IMPACT | Increased Mastery And Professional Application Of Coaching Theory |