| Acronym | Definition |
|---|
| IRIS | Integrated Risk Information System (US EPA) |
| IRIS | Incorporated Research Institutions for Seismology |
| IRIS | Illinois Researcher Information Service (University of Illinois Library at Urbana-Champaign) |
| IRIS | Institut de Relations Internationales et Strategiques (French) |
| IRIS | Immune Reconstitution Inflammatory Syndrome (HIV and AIDS) |
| IRIS | Internet Registry Information Service |
| IRIS | International Railway Industry Standard |
| IRIS | International Research Institute of Stavanger (Norway) |
| IRIS | Immunization Registry Information System |
| IRIS | Insurance Regulatory Information System (NAIC) |
| IRIS | Institute of Robotics and Intelligent Systems (Universidad de Guadalajara; Mexico; also seen as IRSI: Instituto de Robótica y Sistemas Inteligentes) |
| IRIS | Infrared Interferometer Spectrometer |
| IRIS | Infrastructure for Resilient Internet Systems |
| IRIS | Image Recognition Integrated Systems (Belgium) |
| IriS | International Research Institutes |
| IRIS | Internet Router in Space |
| iRIS | Integrated Research Information System |
| IRIS | Interior Redesign Industry Specialist |
| IRIS | Instant Response Information Service (Toshiba support knowledgebase) |
| IRIS | Italian Research Interim Stage |
| IRIS | International Radio Interferometric Surveying |
| IRIS | Internal Rotary Inspection System |
| IRIS | Institute of International and Strategic Studies (Paris) |
| IRIS | Integrated Registration Information System (Hong Kong) |
| IRIS | Instructional Resources Information System |
| IRIS | Integrated Raster Imaging System (workstation from SGI) |
| IRIS | Initiative for Research & Innovation in Science (India) |
| IRIS | Institute for Resource Information Systems (Cornell University) |
| IRIS | Independent Resource and Information Services |
| IRIS | Internally Radiating Impulse Structure (Engine) |
| IRIS | Infrared Imaging Survey |
| IRIS | Imaging, Robotics, and Intelligent Systems laboratory (University of Tennessee) |
| IRIS | Interrogation Requirements Information System |
| IRIS | Institute for Rural Innovation and Stewardship |
| IRIS | Infrared Information Symposium |
| IRIS | Increased Reward with Increased Service |
| IRIS | Infrared Information System |
| IRIS | Internal Revenue Information Service |
| IRIS | Integrated Records Information System |
| IRIS | Infrared Imaging Seeker |
| IRIS | Integrated Reports and Information System (Australia) |
| IRIS | Interactive Retail Information System |
| IRIS | Internet Retailer Information System (SAAB) |
| iRIS | Internet Research Information System |
| IRIS | Institut de Robotique et de Systèmes Intelligents (French: Institute for Robotics and Intelligent Systems; Canada) |
| IRIS | Internal Revenue Information System |
| IRIS | Investment Resource and Information Service (National Library of Singapore) |
| IRIS | Infrared Intrusion Sensor |
| IRIS | Integrated Resource Infrastructure Solutions |
| IRIS | Inspection Reporting Information System |
| IRIS | Internetted Range Interactive Simulations |
| IRIS | Inarihan River Irrigation System (Philippines) |
| IRIS | International Repair Information Service (Electric/electronic repair coding universal) |
| IRIS | Immuno-Deficience Primitive: Recherche, Information, Soutien |
| IRIS | Inter-Region Information Society |
| IRIS | Intelligent Retrieval Information System (Sprint) |
| IRIS | Inferential Retrieval Index System |
| IRIS | International Retrieval Index System |
| IRIS | Imaginons un Réseau Internet Soliataire |
| IRIS | Integrated Reliability Information System |
| IRIS | Integrated Reconnaissance Intelligence System |
| IRIS | International Renal Insufficiency Society |