| Acronym | Definition |
|---|
| IAU | International Astronomical Union |
| IAU | International Association of Universities |
| IAU | Islamic Azad University (Iran) |
| IAU | Internet Acceleration Utility |
| IAU | International Association of Ultrarunners |
| IAU | Internal Affairs Unit (police) |
| IAU | Incremental Analysis Update (computational modeling) |
| IAU | Islamic American University |
| IAU | Installation and Availability Update (Windows) |
| IAU | I Adore You |
| IAU | Integrated Avionics Unit |
| IAU | Intelligence & Analysis Unit (government regulatory agencies) |
| IAU | Infrastructure Accounting Unit |
| IAU | Interface Adapter Unit |
| IAU | Inline Ad Unit (internet advertising) |
| IAU | Instructor Annual Utilization |
| IAU | Internet Application Utility |