| Abbreviation | Definition |
|---|---|
| IAC | Intercollegiate Athletics Committee |
| IACO | Inter Athletic Council of Officials |
| IADA | Illinois Athletic Directors Association |
| IAF | Indoor Athletic Facility |
| IAF | International Athletics Foundation |
| IAFB | Ironbound Athletic Field B |
| IAL | Intercollegiate Athletic Leadership |
| IATA | Indiana Athletic Trainers Association |
| IDFA | International Drug Free Athletics |
| IEAC | Inland Empire Athletic Conference |
| IIAC | Iowa Intercollegiate Athletic Conference |
| IMAA | Indian Mills Athletic Association |
| ISAC | Idol Star Athletic Competition |
| ISAC | International Schools Athletic Conference |
| ISAL | Independent Schools Athletic League |
| ITAT | ImPACT Trained Athletic Trainer |
| ITAT | ImPACT Trained Athletic Trainers |
| IWAA | Incarnate Word Athletic Association |
| JAA | Jericho Athletic Association |
| JAA | Judges Athletic Association |