| Acronym | Definition |
|---|
| CIR | Circle |
| CIR | Committed Information Rate (data communications) |
| CIR | Circumference |
| CIR | Circuit |
| CIR | Color Infrared |
| CIR | Circular |
| CIR | Committed Information Rate (maximum average data rate that a network undertakes under normal circumstances) |
| CIR | Cosmetic Ingredient Review |
| CIR | Circulate |
| CIR | Cost Income Ratio |
| CIR | Center for Investigative Reporting |
| CIR | Center for Individual Rights |
| CIR | Conselho Indígena de Roraima (Portuguese: Indigenous Council of Roraima; Roraima, Brazil) |
| CIR | Consiglio Italiano Per I Rifugiati (Italian Refugee Council) |
| CIR | Center for International Rehabilitation |
| CIR | Channel Impulse Response |
| CIR | Coordinator for International Relations (Japan Exchange and Teaching Programme) |
| CIR | Committee of Interns and Residents |
| CIR | Consumer IR (remote control via infrared) |
| CIR | Carrier-to-Interference Ratio |
| CIR | Carbon Isotope Ratio |
| CIR | Center for Impact Research |
| CIR | Center for Immigration Research |
| CIR | Colegio Interamericano de Radiologia (Inter-American College of Radiology) |
| CIR | Central de Información de Riesgos |
| CIR | Cold-In-Place Recycled |
| CIR | Certified Internet Recruiter (Advanced Internet Recruitment Strategies professional certification) |
| CIR | Collaborative Information Retrieval |
| CIR | Context-based Information Retrieval |
| CIR | Combustion Integrated Rack |
| CIR | Center for Insurance Research |
| CIR | Cargo Integration Review |
| CIR | Central Intelligence Report |
| CIR | Continuous Improvement Review |
| CIR | Complex Impulse Response |
| CIR | Centre Instantané de Rotation |
| CIR | Communication Industry Researchers, Inc. |
| CIR | Comprehensive Inpatient Rehabilitation |
| CIR | Cylindrical Internal Reflection |
| CIR | Cerebral Impulse Relay |
| CIR | Continuing Intelligence Requirement |
| CIR | Critical Information Requirement |
| CIR | Christians in Recovery, Inc. (online support group) |
| CIR | Capital Improvement Report |
| CIR | Coherent Imaging Radar |
| CIR | California Initiative Review |
| CIR | Chair Indicate Release/Refuse |
| CIR | Cost Information Report |
| CIR | Configuration Inspection Report |
| CIR | Change Incorporation Record (NASA) |
| CIR | Change Incorporation Record |
| CIR | Cellule Inter-Agence de Réinsertion (French) |
| CIR | Certificado de Incentivo Forestal (Spanish) |
| CIR | Centre for Innovation and Research |
| CIR | Computer Integrated Repair |
| CIR | Conformity Inspection Record |
| CIR | Continuous Infrared |
| CIR | Critical Information Request |
| CIR | Character Information Repository (Alleria, a role playing game) |
| CIR | Capital Investment Request |
| CIR | Controlled Impact Reentry (package) |
| CIR | Client Infrastructure Representative |
| CIR | Coordinated Implementation Required |
| CIR | Chronic Intermittent Rhabdomyolysis |
| CIR | Critical Implementation Review |
| CIR | Command Incident Report |
| CIR | Calgary Independent Realty Ltd. (Calgary, Aberta, Canada) |
| CIR | Cephalo-Iliac Right |
| CIR | Collection Intelligence Requirement |
| CIR | Centralized Inventory Report |
| CIR | COMSEC INFOSEC Representative |
| CIR | Call Initiate Request |
| CIR | Call Inquiry Response |
| CIR | Candidate Interoperability Plan |
| CIR | Contingency Items Report |
| CIR | Contractor Information Report |
| CIR | Close Indication Relay (electrical circuitry) |