| Acronym | Definition |
|---|
| IAS | International Accounting Standards |
| IAS | International AIDS Society |
| IAS | Internet Authentication Service (remote access security for Windows 2000) |
| IAS | Institute for Advanced Studies |
| IAS | Internet Authentication Service (Microsoft) |
| IAS | International and Area Studies |
| IAS | Invasive Alien Species (APEC subcommittee) |
| IAS | Intra-Americas Sea |
| IAS | Institut d'Astrophysique Spatiale (French) |
| IAS | Intelligent Autonomous Systems |
| IAS | Indian Administrative Service (formerly Indian Civil Service) |
| IAS | International Association of Scientologists |
| IAS | Industry Applications Society (IEEE) |
| IAS | International Association of Sedimentologists |
| IAS | Immigration Advisory Service (UK) |
| IAS | International Aid Services |
| iAS | Internet Application Server (Oracle) |
| IAS | Information Assurance and Security (International Symposium) |
| IAS | Internal Audit Services |
| IAS | Indicated Air Speed |
| IAS | International Auto Salon (Auto Exhibitor Show) |
| IAS | Increased Attack Speed (Diablo) |
| IAS | International Association of Sufism |
| IAS | Internal Anal Sphincter |
| IAS | Intelligence Analysis System |
| IAS | Islamic World Academy of Sciences |
| IAS | Instituto Argentino de Siderurgia (Argentine Institute of Iron and Steel Industry) |
| IAS | Inorganic Arsenic |
| IAS | Immunisation Awareness Society |
| IAS | Image Assessment System |
| IAS | Image Access Solutions |
| IAS | Inertia Active System (Edlebrock auto/motorcycle progressive suspension) |
| IAS | Information Access System |
| IAS | International Aroid Society |
| IAS | Institute of Atmospheric Sciences |
| IAS | Increase Attack Speed (gaming) |
| IAS | In-situ Air Sparging |
| IAS | Integrated Avionics System |
| IAS | Interactive Application System |
| IAS | International Accounting System |
| IAS | Institute for Afghan Studies |
| IAS | International Association of Seismology |
| IAS | Initial Advice Statement |
| IAS | Institute of Aeronautical Sciences |
| IAS | Isobaric Analog State |
| IAS | Industrial Adjustment Services (Canada) |
| IAS | Information Assurance Solutions |
| IAS | Iasi, Romania - Iasi (Airport Code) |
| IAS | Information Access Services |
| IAS | Immediate Access Storage |
| IAS | Integrated Application Solutions (Tekelec) |
| IAS | Intel Audio Studio |
| IAS | It's Always Something |
| IAS | Individual Assignment System (New York Supreme Court) |
| IAS | Impact Assessment Statement |
| IAS | Internal Audio Subsystem |
| IAS | Internal Audit Section (Hong Kong) |
| IAS | International Adhesions Society |
| IAS | Incineration At Sea |
| IAS | Institute for Aerospace Studies |
| IAS | Instrument Air System |
| IAS | Interactive Analysis System |
| IAS | Integrated Automation Solutions |
| IAS | Institute for Applied Socio-Economics |
| IAS | Intra-Abdominal Sepsis |
| IAS | Image Access Service |
| IAS | Institute of Agriculture Sciences (Vietnam) |
| IAS | Islamic Association of Saskatchewan (Canada) |
| IAS | Intra-Atrial Septum (heart) |
| IAS | Integrated AUTODIN System |
| IAS | Integrated Access Switch (Northchurch Comm) |
| IAS | Information Applications and Systems |
| IAS | Institute of Asset Management (UK) |
| IAS | Integrate-And-Square |
| IAS | Indirect Access Service |
| IAS | Ideal Access Structure |
| IAS | Interference Analysis System |
| IAS | Image Annotation Service |
| IAS | Instrument Analog Slice |
| IAS | Infrastructure Architecture Solutions |
| IAS | Inelastic Atom Scattering |
| IAS | Intelligence Analyst Station |
| IAS | International Armaments Strategy |
| IAS | Integrated Accounting/Avionics System |
| IAS | International Association of Seismologists |