| Acronym | Definition |
|---|
| CIS | Commonwealth of Independent States (formerly the USSR) |
| CIS | CompuServe Information Service |
| CIS | Computer Information Systems |
| CIS | Canadian Interuniversity Sport |
| CIS | Citizenship and Immigration Services (US Department of Homeland Security) |
| CIS | Computer and Information Science (University of Pennsylvania) |
| CIS | Contact Image Sensor |
| CIS | Center for International Studies (MIT) |
| CIS | Computer Information Science |
| CIS | Center for Internet and Society (Stanford Law School) |
| CIS | Cluster Ion Spectrometry experiment (Cluster spacecraft) |
| CIS | Canadian Industry Statistics |
| CIS | Catholic Information Service (Knights of Columbus) |
| CIS | Cancer Information Service (National Cancer Institute) |
| CIS | Carcinoma in Situ |
| CIS | Center for Immigration Studies |
| CIS | Center for Internet Security |
| CIS | Customer Information System |
| CIS | Construction Industry Scheme (UK) |
| CIS | Card Information Structure |
| CIS | Centre for International Studies |
| CIS | Centre for Independent Studies (AU) |
| CIS | Clinically Isolated Syndrome |
| CIS | Career Information System |
| CIS | Computational Intelligence and Security (IEEE conference) |
| CIS | Comparative and International Studies (Switzerland) |
| CIS | Council of International Schools |
| CIS | Congressional Information Service |
| CIS | Center for Imaging Science (Johns Hopkins University) |
| CIS | Canadian Ice Service (government agency) |
| CIS | CMOS Image Sensor |
| CIS | Continuous Ink System |
| CIS | Community Information System |
| CIS | Current Index to Statistics |
| CIS | Clinical Information System |
| CIS | Collective Investment Scheme (Citibank) |
| CIS | Confederacy of Independent Systems (Star Wars) |
| CIS | Consular Information Sheets |
| CIS | Composite Information Server (Composite Software Inc.) |
| CIS | Community Innovation Survey |
| CIS | Confederation of Independent States (former Soviet Union) |
| CIS | Citizen Information Service |
| CIS | Cardiovascular Institute of the South |
| CIS | Computational Intelligence Society (IEEE) |
| CIS | Consumer and Industry Services |
| CIS | Bureau of Citizenship and Immigration Services (US Department of Homeland Security) |
| CIS | Component Integration Services |
| CIS | Corporate Identity System |
| CIS | Center for Industrial Services |
| CIS | Corporate Information Services |
| CIS | Copper-Indium-Diselenide |
| CIS | Center for Integrated Systems (Washington Community and Technical Colleges) |
| CIS | Critical Incident Stress |
| CIS | Canadian International School |
| CIS | Communication and Interpersonal Skills |
| CIS | Christians in Science (UK) |
| CIS | Center for Information Services (Washington Community and Technical Colleges) |
| CIS | Cancer Information Specialist |
| CIS | Customs Information System (US Customs) |
| CIS | Chemical Inventory System |
| CIS | Centre International de Sejour |
| CIS | Copenhagen International School |
| CIS | Corporate Information System |
| CIS | Competitive Impact Statement |
| CIS | Content Intelligence Services (Documentum product) |
| CIS | Component Information System |
| CIS | Consumer Information Source (National Association of Insurance Commissioners) |
| CIS | Clinical Immunology Society |
| CIS | Countryside Information System |
| CIS | Course Instructor Survey |
| CIS | Canada Investment and Savings (government) |
| CIS | Combat Intelligence System |
| CIS | Corporate Information Security |
| CIS | Chemical Information System |
| CIS | Copper Indium Selenide (compound semiconductor) |
| CIS | Chinese International School |
| CIS | Cerberus' Internet Scanner |
| CIS | Communication Information Systems (SHAPE) |
| CIS | Communications & Information Systems |
| CIS | Centro de Intercambio y Solidaridad (Center for Exchange and Solidarity) |
| CIS | Central Information System |
| CIS | Community Information Service |
| CIS | Center for Islam and Science |
| CIS | Continuous Injection System |
| CIS | Central Index System |
| CIS | Co-operative Insurance Society, Ltd. (UK) |
| CIS | Customer Interaction Software |
| CIS | Cops in Schools |
| CIS | Cargill Investor Services |
| CIS | Computational and Information Sciences |
| CIS | Center for Instructional Support |
| CIS | Centre International d'Informations de Sécurité et de Santé au Travail (French: International Occupational Safety and Health Information Centre; Switzerland) |
| CIS | Comunita degli Stati Indipendenti (Italian: Commonwealth of Independent States) |
| CIS | Center for Insect Science (University of Arizona) |
| CIS | Centre for Intercultural Studies |
| CIS | Command Information System |
| CIS | Central Intelligence Service (Privateer 2 PC game) |
| CIS | CASE Integration Services |
| CIS | Colombo International School (Sri Lanka) |
| CIS | Cancer Information System |
| CIS | Content Integration Server |
| CIS | Company Information System |
| CIS | Construction Information Sources |
| CIS | Crime Information System |
| CIS | Collection Information System |
| CIS | Conference of Independent Schools of Ontario |
| CIS | Chartered Institute of Secretaries |
| CIS | Center for Ignatian Spirituality (Los Angeles) |
| CIS | Cluster Ion Spectrometer |
| CIS | Composite Image Systems |
| CIS | Component Interface Specification |
| CIS | Civil Society Initiative (WHO) |
| CIS | Comunidad Israelita de Santiago |
| CIS | Computer Information Service |
| CIS | Citicorp Investment Services |
| CIS | Curriculum and Instructional Services |
| CIS | Center for Ideas and Society |
| CIS | Criminal Information System |
| CIS | City Information Systems |
| CIS | Catering International and Services |
| CIS | Conventional Inertial System |
| CIS | China Inspection Services (Beijing, China) |
| CIS | Communites in Schools |
| CIS | Certification Information Service |
| CIS | Corinthian Internet Services (AU) |
| CIS | Continuous Improvement System (total quality management system) |
| CIS | Carlisle Indian School (Pennsylvania) |
| CIS | Contracts Information System |
| CIS | Californians for Inclusive Schools |
| CIS | Card Information Services |
| CIS | Communication Interface System |
| CIS | Certified Investment Specialist |
| CIS | Combat Information System |
| CIS | Corrections Information System |
| CIS | Core Integration System |
| CIS | College Independent Study |
| CIS | Commemorative Integrity Statement (Canada) |
| CIS | Correspondence Imaging System |
| CIS | Catalogue Item Subscription |
| CIS | Combined Influence Sweep |
| CIS | Communities in Schools Academy (Durham, NC) |
| CIS | Commercial Industrial Services |
| CIS | Card Information System |
| CIS | Class Interface Size |
| CIS | Comptroller Information System |
| CIS | Conductor Insulator Semiconductor |
| CIS | Containment Isolation System |
| CIS | Common Item Support |
| CIS | Castelli International School |
| CIS | communications interface shelter (US DoD) |
| CIS | Centre for Intergroup Studies (University of Cape Town, South Africa) |
| CIS | Combat Identification System |
| CIS | Chemical Injection System |
| CIS | Continuous and Intermittent Simulation (auditing) |
| CIS | Center for Injury Sciences (University of Alabama at Birmingham) |
| CIS | Customized Information System |
| CIS | Combat Instruction Set |
| CIS | Certified Investment Strategist |
| CIS | Cast Iron Sleeve (engine part) |
| CIS | Career Information Specialist |
| CIS | Central Iowa Symphony (Ames, IA) |
| CIS | Customer Interface System |
| CIS | Contact Image Sensing (scanner technology) |
| CIS | Contractor's Information Submittal |
| CIS | Control Indicator Set |
| CIS | Central IFF System |
| CIS | Codefusion Internet Services |
| CIS | Central Integration Site |
| CIS | Central Integration Site (NASA) |
| CIS | Chemical Imaging System |
| CIS | Command Instrument System (aviation) |
| CIS | Consolidated Investment Services Inc. |
| CIS | Change Impact Summary |
| CIS | Chair Indicate Stopped |
| CIS | Center for Imaging and Sensing (WPI Metal Processing Institute, Worcester, MA) |
| CIS | Component Identification Sheet |
| CIS | Clinical Information Study |
| CIS | Contractor Information Service |
| CIS | Canadian Inspection Service |
| CIS | Contractor Information Systems |
| CIS | Contract Instruction Services |
| CIS | Community and Industry Services |
| CIS | Career Information Services, Inc (Atlanta, GA) |
| CIS | Catalogue Interoperability Subsystem |
| CIS | Commercial Imagery Strategy |
| cis | Cosine plus i (imaginary number) sine |
| CIS | Core Instrumentation Subsystem |
| CIS | Contel Information Systems Incorporated |
| CIS | Cochannel Interference Suppression |
| CIS | Communications Interface Specification |
| CIS | Colliery Information System (UK) |
| CIS | Corrosion Inhibiting Substance |
| CIS | Characteristic Isochromat Spectroscopy |
| CIS | Convergent Internet Solutions LLC |
| CIS | CASE Information Services |
| CIS | Computer Intrusion Section (FBI) |
| CIS | Catalytic Investment Strategy |
| CIS | Communications Information Software, Inc. |
| CIS | Custom Internet Solutions, Inc. |
| CIS | Container Identification System |
| CIS | Council on Invasive Species |
| CIS | Cell Input Switch |
| CIS | Computer Intelligence System |
| CIS | Critical Information Shortfall |
| CIS | Certificate Issuance Software |
| CIS | Combat Integration/Identification System |
| CIS | Combat Intelligence Squadron |
| CIS | Cryptologic Interface Station |
| CIS | Creative Intelligent Systems (Workshop) |
| CIS | Corporate Implementation System |
| CIS | Centre d'informations Scientifiques (French: Center for Scientific Information) |