| Acronym | Definition |
|---|
| ION | Illinois Online Network (community colleges) |
| ION | Institute Of Navigation |
| ION | In Other News |
| ION | Institute of Neurology |
| ION | Ionian (linguistics) |
| ION | Institute of Neuroscience |
| ION | Institute of Nanotechnology (UK) |
| ION | Intelligent Object Network |
| ION | Integrated on-Demand Network |
| ION | Internetworking over Nbma |
| ION | Information and Operational Notice |
| ION | Input Output Nodes |
| ION | Institute of Nutrition |
| ION | Index to Organism Names |
| ION | Internetworking Over NBMA (Non-Broadcast, Multi-Access) |
| ION | Integrated On-demand Network (Sprint FastBreak) |
| ION | Institute of Optimum Nutrition (UK) |
| ION | Item of Note |
| ION | Inferior Olivary Nucleus |
| ION | IDL On the Net |
| ION | International Ocean Network |
| ION | Intelligent Optical Networking (Project) |
| ION | Inter Office Note |
| ION | Internship Opportunities Now |
| ION | Infringement offence notice ( |
| ION | Infringement Offence Notice (police incident code; New Zealand) |
| ION | International Order of Nitrogen |
| ION | Institute for Optimal Nutrition (USA) |
| ION | Individuals, Organizations and Networks (coined by Bernie Slepkov of DreamTEAMS International) |
| ION | International Optical Networks |
| ION | Information Operations Navigator |
| ION | Independent Overlay Network |