| Acronym | Definition |
|---|
| IOS➣Internetwork Operating System |
| IOS➣Institute of Software (Chinese Academy of Sciences) |
| IOS➣International Organization for Standardization |
| IOS➣Issues of Substance (Canada) |
| IOS➣Index of Services (service industries; various locations) |
| IOS➣Independent On Sunday |
| IOS➣Isles of Scilly |
| IOS➣iPhone Operating System (Apple) |
| IOS➣Institute of Swimming (UK) |
| IOS➣Internal Oversight Service (UN) |
| IOS➣Integrative Organismal Systems (various organizations) |
| IOS➣Internet Operating System |
| IOS➣International Opera Studio (Zurich, Switzerland) |
| IOS➣Input Output Subsystem |
| IOS➣Input Output System |
| IOS➣Intel Online Services |
| IOS➣Input Output Supervisor |
| IOS➣Institute of Statisticians (est. 1948; now Royal Statistical Society; UK) |
| IOS➣Institute of Ocean Sciences (Canada) |
| IOS➣Isle of Springs (Maine) |
| IOS➣Interior Office of the Solicitor (US DOI) |
| IOS➣Instructor Operator Station |
| IOS➣Institute of Sociology |
| IOS➣Institute of Oceanographic Sciences |
| IOS➣Is ook schitterend (Dutch band) |
| IOS➣Instructor Operating Station |
| IOS➣Interorganizational System |
| IOS➣Internet Office Suite (software) |
| IOS➣International Outsourcing Services |
| IOS➣Internet Over Satellite |
| IOS➣Illinois Orchid Society (est. 1952) |
| IOS➣Input/Output Subsystem |
| IOS➣Institute of Objective Studies (India) |
| IOS➣International Organization for Standards |
| IOS➣Interorganizational Information System |
| IOS➣Integrated Observing System |
| IOS➣Input/Output Supervisor |
| IOS➣Institute for Optical Sciences (University of Toronto; Canada) |
| IOS➣Integrated Office System |
| IOS➣I'm Only Sleeping (Beatles song) |
| IOS➣Ilheus, Bahia, Brazil - Eduardo Gomes (Airport Code) |
| IOS➣Insurance Overload Staffing (Dallas, TX) |
| IOS➣Intelligence Operations Specialist (US Federal Bureau of Investigation) |
| IOS➣International Online Soccer (gaming, Half-Life modification) |
| IOS➣Institute for Orgonomic Science |
| IOS➣International Oak Society |
| IOS➣Internet Ophthalmology Society |
| IOS➣Inter-Operability Specification |
| IOS➣Initial Operational System |
| IOS➣International Officer School |
| IOS➣Inter-Operability Standard |
| IOS➣Integrated Observation System |
| IOS➣Igoss Observing System |
| IOS➣International Operator Services (Sprint) |
| IOS➣Interim Operational Supplement |
| IOS➣Indian Ocean Tracking Station (AFSCN) |
| IOS➣Inventory Of Service |
| IOS➣Intranet Operating System |
| IOS➣Internal Order System |
| IOS➣Inspired of Spirit (online forum) |
| IOS➣Illinois Orthopaedic Society |
| IOS➣Inter-Organizations Section |
| IOS➣Integrated Operational Services |
| IOS➣Intelligence Operations System (USMC replacement for TCO and IAS Suites) |
| IOS➣Intermediate Open System |
| IOS➣Interconnected Operating System |
| IOS➣Inactive, Obsolete, Surplus (jobs) |
| IOS➣Individual Ordinance Summary |
| IOS➣Integrated Operations Scenario |
| IOS➣Improved Oceanographic Sensor |
| IOS➣Internal Opportunity System (Motorola) |
| IOS➣Initial Operating Sector |
| IOS➣Interim Operational System |
| IOS➣Infinity Optical Systems |
| IOS➣Integrated Outsourcing Services GmbH (Germany) |