| Acronym | Definition |
|---|
| CLS | Class (Air Force) |
| CLS | Community Legal Service |
| CLS | Commission on Life Sciences (NAS) |
| CLS | Common Language Specification (Microsoft .NET; set of conventions intended to promote language interoperability) |
| CLS | Continuous Linked Settlement (banking) |
| CLS | Columbia Law School |
| CLS | Canadian Light Source, Inc. (Saskatoon, Saskatchewan, Canada) |
| CLS | Collecte Localisation Satellites (French) |
| CLS | Critical Legal Studies |
| CLS | Centre for Labour Market and Social Research (Denmark) |
| CLS | Contrat Local de Sécurité (French: Local Security Contract) |
| CLS | Combat Lifesaver |
| CLS | Coffin-Lowry Syndrome |
| CLS | Contractor Logistic(s) Support |
| CLS | Corporate Learning Systems |
| CLS | Common Levels of Support |
| CLS | Contract Logistics Support |
| CLS | Constrained Least Squares |
| CLS | Cloud Lidar System |
| CLS | Connectionless Server (Siemens/Stromberg-Carlson) |
| CLS | Concordia Lutheran Seminary (Edmonton, Alberta, Canada) |
| CLS | Cisco Link Services |
| CLS | Central Locating Service |
| CLS | Coach Limousine Service (France) |
| CLS | Control Loading System |
| CLS | contracted logistic support (US DoD) |
| CLS | Contingency Landing Site |
| CLS | Career Level School (USMC) |
| CLS | Clean Stocker |
| CLS | Cenani-Lenz Syndactyly |
| CLS | Customer Logistics Support |
| CLS | Central Login Service (University of Cincinnati; Ohio) |
| CLS | Clinical Lipid Specialist |
| CLS | Characteristic Loss Spectroscopy |
| CLS | Comptoir Lyonnais de Soudage (French welding supply company) |
| CLS | Center for Longitudinal Studies (UK) |
| CLS | Concrete Lined Steel (piping) |
| CLS | Soft Clam (FAO species code) |
| CLS | Compton Light Source |
| CLS | Chemistry and Laser Sciences Division |
| CLS | Cooling Loop Simulator |
| CLS | Centi Long Sword (Everquest) |
| CLS | Circadian Lighting System |
| CLS | Capsule Launcher Subsystem |
| CLS | Class of Service restriction (telecom) |
| CLS | Combat Logistics System |
| CLS | Consumer Location System |
| CLS | Collect Localization Satellites |
| CLS | Categories, Lists and Navigation Templates (Wikimedia Foundation) |
| CLS | Collect and Localization by Satellite |
| CLS | Core Logic Server |
| CLS | Combined Link Set (CCS #7) |
| CLS | Coastguard Launching Station |
| CLS | Coupe Leicht Sportlich (Mercedes Benz model) |
| CLS | Classified Logistic Shipment |
| CLS | Car Lux Service (French car rental company) |
| CLS | Cylinder Leaky Wave |
| CLS | Collector Lane Shift |
| CLS | Canadian Listing Service (Canada) |
| CLS | Control Level Schedule (engineering) |
| CLS | Center for Literary Studies |
| CLS | Consolidated Laboratory Services (Van Nuys, CA) |
| CLS | Christian Legal Society |
| CLS | Clear Lake Symphony (Nassau Bay, TX) |
| CLS | Campus Life Services (various schools) |
| CLS | Command & Launch System (defense system) |
| CLS | Clinical Laboratory Scientist |
| CLS | Chief of the Land Staff (Canadian Forces) |
| CLS | Center for Language Studies |
| CLS | Contact Lens Store |
| CLS | Celestica (stock symbol) |
| CLS | Certified Lotus Specialist |
| CLS | Canadian Lumber Standards |
| CLS | Capsule Launch System |
| CLS | Clear Screen |
| CLS | Close |
| CLS | Closed Loop Support |
| CLS | Closed Loop System |
| CLS | Capital Legal Services (Russia) |
| CLS | Chicago Linguistics Society |
| CLS | Cardiac Life Support |
| CLS | Criminal Law Section (various organizations) |
| CLS | Charlotte Latin School |
| CLS | Contact Lens Spectrum (publication) |
| CLS | Client Ledger System (software) |
| CLS | Carton Live Storage |
| CLS | Cargo Loading System |
| CLS | Company Limited by Shares (law) |
| CLS | Central Liabilities System |
| CLS | Center for Leadership and Service (various schools) |
| CLS | Call Logging System |
| CLS | Child Labour Survey |
| CLS | Chinese Language Society |
| CLS | Certified Lubrication Specialist (Society of Triboligy and Lubrication Engineers) |
| CLS | Certified Leasing Specialist |
| CLS | Caterpillar Logistics Services (various locations) |
| CLS | Child Life Specialist |