| Acronym | Definition |
|---|
| IIO➣Independent Investigations Office (British Columbia, Canada) |
| IIO➣Inverse Interest Only |
| IIO➣Immigration Information Officers (US Department of Homeland Security) |
| IIO➣Indian Inventors' Organization |
| IIO➣Initial Investigating Officer |
| IIO➣Interallied Insurance Organization |
| IIO➣Inertial Instrument/Instrumentation Organization/Operation |
| IIO➣International Intergovernmental Organization |