| Acronym | Definition |
|---|
| CIR | Circle |
| CIR | Circumference |
| CIR | Committed Information Rate (data communications) |
| CIR | Circuit |
| CIR | Circular |
| CIR | Circulate |
| CIR | Committee on International Relations (various organizations) |
| CIR | Cosmetic Ingredient Review |
| CIR | Certificate in International Relations (various organizations) |
| CIR | Comprehensive Immigration Reform |
| CIR | Committed Information Rate (maximum average data rate that a network undertakes under normal circumstances) |
| CIR | Channel Impulse Response |
| CIR | Center for Interdisciplinary Research (various locations) |
| CIR | Cambridge Investment Research (various locations) |
| CIR | Color Infrared |
| CIR | Committee on Information Resources (Triangle Research Libraries Network; North Carolina) |
| CIR | Center for Investigative Reporting |
| CIR | Cost Income Ratio |
| CIR | Combustion Integrated Rack |
| CIR | Commissioner of Inland Revenue (various locations) |
| CIR | Central Intelligence Report |
| CIR | Crédit d'Impôt Recherche (French: Research Tax Credit) |
| CIR | Consumer IR (remote control via infrared) |
| CIR | Cox, Ingersoll and Ross (economic model) |
| CIR | Committee of Interns and Residents |
| CIR | Certified Internet Recruiter (Advanced Internet Recruitment Strategies professional certification) |
| CIR | Compagnie Industriali Riunite (Italian industrial group) |
| CIR | Comprehensive Inpatient Rehabilitation |
| CIR | Color Infra Red |
| CIR | Comprehensive Information Report |
| CIR | Current Instruction Register |
| CIR | Consumer Infra Red |
| CIR | Carbon Infra Red |
| CIR | Connector for Infra Red |
| CIR | Committed Information Rate |
| CIR | Carrier to Interference Ratio |
| CIR | Central Indian Ridge (geology) |
| CIR | Center for Individual Rights |
| CIR | Conselho Indígena de Roraima (Portuguese: Indigenous Council of Roraima; Roraima, Brazil) |
| CIR | Centre for Immune Regulation (University of Oslo; Norway) |
| CIR | Consiglio Italiano Per I Rifugiati (Italian Refugee Council) |
| CIR | Continuous Infrared |
| CIR | Critical Information Requirement |
| CIR | Chicago Indoor Racing (Illinois) |
| CIR | Continuous Improvement Review |
| CIR | Coordinator for International Relations (Japan Exchange and Teaching Programme) |
| CIR | Complex Impulse Response |
| CIR | Carrier-to-Interference Ratio |
| CIR | Center for International Rehabilitation |
| CIR | Command Instrument Rating (flight training) |
| CIR | Certificate in Institutional Research (various schools) |
| CIR | Cold In-Place Recycling (pavement processing and treatment) |
| CIR | Centre d'Information et de Recrutement (French: Information and Recruitment Center; law enforcement) |
| CIR | Chinese Information Retrieval |
| CIR | Community Information Referral (Arizona) |
| CIR | Consortium for International Recruitment (European Council of International Schools) |
| CIR | Cost Information Report |
| CIR | Convention des Institutions Républicaines (French political party) |
| CIR | Community Impact Report (various locations) |
| CIR | Critical Infrastructure Resiliency (US FEMA) |
| CIR | Common Intermediate Representation (computing) |
| CIR | Carbon Isotope Ratio |
| CIR | Collections Information Repository (US Department of the Treasury) |
| CIR | Center for Impact Research |
| CIR | Colegio Interamericano de Radiologia (Inter-American College of Radiology) |
| CIR | Central de Información de Riesgos |
| CIR | Center for Immigration Research |
| CIR | Center for Insurance Research |
| CIR | Collaborative Information Retrieval |
| CIR | Context-based Information Retrieval |
| CIR | Cloud Infrared Radiometer |
| CIR | Client Infrastructure Representative |
| CIR | Cargo Integration Review |
| CIR | Compte Individuel Retraite (French: Individual Retirement Account) |
| CIR | Close Indication Relay (electrical circuitry) |
| CIR | Chemical Industry Roundtable |
| CIR | Cross Index Range |
| CIR | Centre Instantané de Rotation |
| CIR | Communication Industry Researchers, Inc. |
| CIR | Clinical Intelligence Rules |
| CIR | Constructions Industrielles du Rhône (French industrial construction company) |
| CIR | Cylindrical Internal Reflection |
| CIR | Cerebral Impulse Relay |
| CIR | Continuing Intelligence Requirement |
| CIR | Compagnie Immobilière de Restauration (French real estate company) |
| CIR | Christians in Recovery, Inc. (online support group) |
| CIR | Capital Improvement Report |
| CIR | Coherent Imaging Radar |
| CIR | California Initiative Review |
| CIR | Channel Islands Restoration (Santa Barbara, CA) |
| CIR | Chair Indicate Release/Refuse |
| CIR | Change Incorporation Record |
| CIR | Configuration Inspection Report |
| CIR | Centre Informatique Recherche (French computer research center) |
| CIR | Change Incorporation Record (NASA) |
| CIR | Cellule Inter-Agence de Réinsertion (French) |
| CIR | Certificado de Incentivo Forestal (Spanish) |
| CIR | Centre for Innovation and Research |
| CIR | Conformity Inspection Record |
| CIR | Computer Integrated Repair |
| CIR | Code de l'Impôt sur les Revenus (French: Income Tax Code; Belgium) |
| CIR | Capital Investment Request |
| CIR | Critical Information Request |
| CIR | Character Information Repository (Alleria, a role playing game) |
| CIR | Controlled Impact Reentry (package) |
| CIR | Coordinated Implementation Required |
| CIR | Chronic Intermittent Rhabdomyolysis |
| CIR | Critical Implementation Review |
| CIR | Calgary Independent Realty Ltd. (Calgary, Aberta, Canada) |
| CIR | Command Incident Report |
| CIR | Call Inquiry Response |
| CIR | Centralized Inventory Report |
| CIR | COMSEC INFOSEC Representative |
| CIR | Call Initiate Request |
| CIR | Candidate Interoperability Plan |
| CIR | Cephalo-Iliac Right |
| CIR | Collection Intelligence Requirement |
| CIR | Centre d'Intervention Rapide (French: Rapid Intervention Center; emergency medical transportation) |
| CIR | Carrier-Induced Regeneration (bioengineering) |
| CIR | Contractor Information Report |
| CIR | Contingency Items Report |
| CIR | Critical Inspection Report (US Coast Guard) |