| CSE | Council of Science Editors | In English | → Organizations and associations → Mathematics and natural sciences → Graphic industries, printing, publishing |
| CSE | Communications Security Establishment = CST | Centre de la Ssécurité des Télécommunications | In French |
In English | → Telecommunications |
| CSE | Centre for Sustainable Energy | In English | → 5023 → Energy economics |
| CSEG | Conseil Supérieur de l’Électricité et du Gaz | In French | → Energy economics → Electrical engineering |
| CSEP | Cornwall Sustainable Energy Partnership | In English | → Energy economics |
| CSF | Cerebrospinal fluid | In English | → Anatomy → Physiology |
| CSG | Centre Spatial Guyanais | In French | → Spaceflight engineering, astronautics |
| CSI | Cité des Sciences et de l'Industrie | In French | → Museums → Mathematics and natural sciences |
| CSICOP | Committee for the Scientific Investigation of Claims of the Paranormal | In English | |
| CSIPMH | Center for the Study of Issues in Public Mental Health | In English | → Psychology → Psychiatry |
| CSIRO | Commonwealth Scientific and Industrial Research Organization (www.csiro.au) | In English | → Organizations and associations → International relations → Research policy → Engineering, technology |
| CSIS | Conseil Stratégique des Industries de Santé | In English | → Organizations and associations → Medicine → Pharmacology, toxicology |
| CSMA/CD | Carrier Sense Multiple Access with Collision Detection | In English | → Telecommunications |
| CSNE | Comité Sûreté Nucléaire en Exploitation | In French | → Nuclear technology |
| CSOC | Consolidated Space Operations Center | In English | → Spaceflight engineering, astronautics |
| CSOEC | Conseil Supérieur de l'Ordre des Experts-Comptables | In French | → Organizations and associations → Commercial law → Accounting |
| CSP | Conseil Supérieur de la Pêche | In French | → Organizations and associations → Fishing, hunting |
| CSP | Comité des Spécialités Pharmaceutiques | In French | → Organizations and associations → Pharmacology, toxicology |
| CSR | Chemical Safety Report | In English | → Chemical technology → Chemistry |
| CSRP | Chambre Syndicale de la Répartition Pharmaceutique | In French | → Organizations and associations → Pharmacology, toxicology |
| CSRT | Conseil Supérieur de la Recherche et de la Technologie | In French | → Research policy → Engineering, technology |
| CSRT | Conseil Supérieur de la Recherche et des Technologies | In French | → Mathematics and natural sciences |
| CSS | Certificat de Sécurité et de Sauvetage | In French | → Medicine |
| CSSIN | Conseil Supérieur de la Sûreté et de l’Information Nucléaire | In French | → Organizations and associations → Nuclear technology |
| CSSP | Circuits Systems and Signal Processing | In English | → Serial publications, periodicals → Telecommunications |
| CSST | Centro Studi sui Sistemi di Trasporto | In Italian | → Vehicle engineering → Transport and postal services |
| CST | Centre de la Ssécurité des Télécommunications = CSE (look above) |
In French | → Telecommunications |
| CSTA | Chambre Syndicale du Transport Aérien | In French | → Organizations and associations → Transport and postal services |
| CSTAR | Continuous Stellar-Tracking Attitude Reference | In English | → Spaceflight engineering, astronautics |
| CSTB | Centre Scientifique et Technique du Bâtiment | In French | → Building |
| CSTC | Consolidated Space Test Center | In English | → Spaceflight engineering, astronautics |
| CSTC | Centre Scientifique et Technique de la Construction = WTCB | Wetenschappelijk en Technisch Centrum voor het Bouwbedrijf | In Dutch |
In French | → Building |
| CSTEP | Comité Scientifique, Technique et Économique de la Pêche | In French | → Organizations and associations → Fishing, hunting |
| CSTI | Conseil Stratégique des Technologies de l’Information | In French | → Organizations and associations → Computer science → Telecommunications |
| CSTI | Culture scientifique, technique et industrielle | In French | → Civilization, culture, progress → Mathematics and natural sciences |
| CSUE | Centro de Satélites de la Unión Europea (www.eusc.europa.eu) = EUSC | European Union Satellite Centre | In English = CSUE | Centro Satellitare dell'Unione Europea | In Italian |
In Spanish | → European Union → Spaceflight engineering, astronautics |
| CSUE | Centro Satellitare dell'Unione Europea (www.eusc.europa.eu) = EUSC (look above) |
In Italian | → European Union → Spaceflight engineering, astronautics |
| ČT | Česká Televize (www.ceskatelevize.cz) | In Czech | → Telecommunications |
| CTA | Clinical Trial Application | In English | → Pharmacology, toxicology |
| CTAA | Centre Technique d'Aide aux Associations | In French | → Associations |
| CTAAI | Commission Territoriale d'Attribution des Aides à l'Innovation | In French | → Research policy → Engineering, technology |
| CTBTO | Comprehensive Nuclear-Test-Ban Treaty Organization | In English | → Organizations and associations → International relations → Nuclear technology |
| CTEU | Centre de Télé-Enseignement Universitaire | In French | → Higher education, universities → Telecommunications |
| CTF | Commit To Flight | In English | → Aeronautics, aircraft → Spaceflight engineering, astronautics |
| CTFT | Centre Technique Forestier Tropical | In French | → Forestry |
| CTG | Conseil Technique Gaz | In French | → Energy economics |
| CTH | Conseiller pour les Travailleurs Handicapés | In French | → Labour, labour economics → Medicine |
| CTI | Commission des Titres d'Ingénieur | In French | → Specialized or (poly)technical colleges → Engineering, technology |
| CTI | Comitato Termotecnico Italiano | In Italian | → Mechanical engineering |
| CTI | Centre Technique Industriel | In French | → Engineering, technology |
| CTI | Computer Telephony Integration | In English | → Computer science → Telecommunications |
| CTI | Couplage Téléphonie Informatique | In French | → Computer science → Telecommunications |
| CTI | Cooling Technology Institute Home (www.cti.org) | In English | → Organizations and associations |
| CTI | Céramiques Techniques et Industrielles (www.ctisa.fr) | In French | |
| CTIBO | Capacity Building of Chinese Technological Intermediary Business Organisations | In English | → Trade → Engineering, technology |
| CTICM | Centre Technique Industriel de la Construction Métallique | In French | → Civil engineering → Building |
| CTIFL | Centre Technique Interprofessionnel des Fruits et Légumes | In French | → Agricultural sciences |
| CTIT | Centrum voor Telematica en Informatica Technologie | In Dutch | → Computer science → Telecommunications |
| CTM | Cordless Terminal Mobility | In English | → Telecommunications |
| CTNERHI | Centre Technique National d'Études et de Recherches sur les Handicaps et les Inadaptations | In French | → Social sciences → Medicine |
| CTP | Comité Technique Paritaire | In French | → Engineering, technology |
| CTP | Centre Technique du Papier (www.webctp.com) | In French | → Research institutes → Paper and board industry |
| CTS | Centre de Transfusion Sanguine | In French | → Blood and circulatory system |
| CTS | Communications Technology Satellite | In English | → Spaceflight engineering, astronautics → Telecommunications |
| CTS | Canadian Technology Satellite | In English | → Spaceflight engineering, astronautics |
| CTS | Comprehensive Transponder Systems | In English | → Telecommunications |
| CTS | Centre des Techniques Spatiales | In French | → Spaceflight engineering, astronautics |
| CTSC | Centre Technique des Salaisons et Conserves | In French | → Agricultural sciences |
| CTTB | Centre Technique des Tuiles et Briques | In French | → 666 |
| CUAMM | Collegio Universitario Aspiranti e Medici Missionari | In Italian | → Specialized or (poly)technical colleges → Medicine |
| CUDI | Corporación Universitaria para el Desarrollo de Internet | In Spanish | → Computer science → Telecommunications |
| CUE | Command Uplink Electronics | In English | → Electronics |
| CUED | Cambridge University Engineering Department (www.eng.cam.ac.uk) | In English | → 278 → Engineering, technology |
| CUH | Code de l'Urbanisme et de l'Habitation | In French | → Public administration, government → Building → Regional planning |
| CUMA | Coopérative d'Utilisation du Matériel Agricole | In French | → Organizations and associations → Agricultural sciences |
| CUMA | Coopérative d’Utilisation de Matériel Agricole | In French | → Organizations and associations → Agricultural sciences |
| CUP | Cambridge University Press | In English | → Higher education, universities → Graphic industries, printing, publishing |
| CUP | Canadian University Press | In English | → Higher education, universities → Graphic industries, printing, publishing |
| CUTE | Clean Urban Transport Europe | In English | → Vehicle engineering → Transport and postal services |
| CUTEC | Clausthaler Umwelttechnik-Institut | In German | → Nature → Environment, environmental sciences → Agricultural sciences |
| CV-ATOD | Centro Virtual de Información sobre Alcohol, Tabaco y otras Drogas = VC-ATOD | Virtual Clearinghouse on Alcohol, Tobacco, and Other Drugs | In English |
In Spanish | → Networks, communication → Medicine |
| CVCEP | Commission de Vérification des Comptes des Entreprises Publiques | In French | → Accounting |
| CVCS | Chemical and Volume Control System | In English | → Nuclear technology |
| CVDC | Cambridge Vehicle Dynamics Consortium | In English | → Organizations and associations → Vehicle engineering |
| CWC | Chemical Weapons Convention = CAQ | Convención sobre las Armas Químicas | In Spanish = CAC | Convention sur les Armes Chimiques | In French = CAQ | Convenção sobre Armas Químicas | In Portuguese |
In English | → International relations → Military engineering |
| CWDM | Coarse Wavelength Division Multiplexing | In English | → Networks, communication → Telecommunications |
| CWE | Caution and Warning Electronics | In English | → Electronics |
| CWEA | Caution and Warning Electronic(s) Assembly | In English | → Electronics |
| CWEU | Caution and Warning Electronic(s) Unit | In English | → Electronics |
| CWL | Cardiff International Airport (www.cwlfly.com) | In English | → Transport and postal services → Aeronautics, aircraft |
| CWSU | Condensate Water Servicing Unit | In English | → Environmental technology, water supply, waste management |
| CYSDV | Cucurbit Yellow Stunting Disorder Virus | In English | → Virology → Agricultural sciences |
| CYSF | Cape York Space Facility | In English | → Astronomy → Spaceflight engineering, astronautics |
| CyT | Ciencia y Tecnología = S&T | Science and Technology | In English = S&T | Sciences et Technologie | In French = C&T | Ciência e Tecnologia | In Portuguese |
In Spanish | → Mathematics and natural sciences → Engineering, technology |
| DA | Douleur Abdominale | In French | → Pathology |
| DAA | Diplôme d'Agronomie Approfondie | In French | → Specialized or (poly)technical colleges → Agricultural sciences |
| DAB | Digital Audio Broadcasting | In English | → Telecommunications |
| DABM | Defense Against Ballistic Missiles | In English | → 355 → Military engineering |
| DAC | Digital-To-Analog Converter | In English | → Computer science → Electronics |
| DAD | Détecteur Autonome Déclencheur | In French | → Electrical engineering |
| DADS | Dual Air Density Satellite | In English | → Spaceflight engineering, astronautics |
| DAG | Diplôme d'Agronomie Générale | In French | → Specialized or (poly)technical colleges → Agricultural sciences |
| DAHW | Deutsche Lepra- und Tuberkulosehilfe | In German | → Organizations and associations → Pathology |
| DAI | Détection Automatique d'Incident | In French | → Image processing → Transport and postal services |
| DAIS | Data Avionics Information System | In English | → Data → Aeronautics, aircraft |
| DAM | Double-Aluminized Mylar | In English | → Chemical technology |
| DAM | Direction des Applications Militaires | In French | → Military engineering |
| DAMA | Demand Assigned Multiple Access | In English | → Telecommunications → Spaceflight engineering, astronautics |
| DANASAT | Direct-Ascent Nuclear ASAT | In English | → Nuclear technology |
| DANCE | Département Appui à la Négociation pour la Commercialisation de l'Électricité | In French | → Electrical engineering |
| DAP | Décodage Acoustico-Phonétique | In French | → Computer-based techniques → Telecommunications → Linguistics |
| DAPO | Direction des Approvisionnements de la Poste | In French | → Transport and postal services |
| DARA | Deutsche Agentur für Raumfahrtangelegenheiten | In German | → Organizations and associations → Astronomy → Spaceflight engineering, astronautics |
| DAS | Digital Avionics System | In English | → Computer-based techniques → Aeronautics, aircraft |
| DASES | Direction de l'Action sociale, de l'Enfance et de la Santé | In French | → Public administration, government → Social welfare → Education → Medicine |
| DASS | Direction de l'Action Sanitaire et Sociale | In French | → Public administration, government → Social welfare → Medicine |
| DAT | Déclaration d'Achèvement des Travaux | In French | → Civil engineering → Building |
| DAT | Direction des Armements Terrestres | In French | → Public administration, government → Military engineering |
| DATR | Directement Affecté aux Travaux sous Rayonnements | In French | → Nuclear technology |
| DAV | Deutscher Apotheker Verlag (www.deutscher-apotheker-verlag.de) | In German | → Organizations and associations → Pharmacology, toxicology |
| DAVF | Dural arteriovenous fistulae = FAVD | Fistule Durale Artérioveineuse Intracrânienne | In French |
In English | → Pathology → Neurology |
| DBG | Deutsche Bodenkundliche Gesellschaft (www.dbges.de) | In German | → Organizations and associations → Agricultural sciences |
| DBW | Differential Ballistic Wind | In English | → Military engineering |
| DC | Delta Clipper | In English | → Aeronautics, aircraft → Spaceflight engineering, astronautics |
| DCA | Defense Communications Agency | In English | → 355 → Telecommunications |
| DCA | Defense Communication Agency | In English | → 355 → Telecommunications |
| DCAA | Defense Contract Audit Agency | In English | → 355 → Military engineering |
| DCAN | Direction des Constructions et Armes navales | In French | → Public administration, government → Military engineering |
| DCAT | Diesel Clean Advanced Technology | In English | → Vehicle engineering |
| DCE | Data and Control Electronics | In English | → Electronics |
| DCE | Data Circuit-terminating Equipment | In English | → Data → Telecommunications |
| DCEA | Digital Control Electronics Assembly | In English | → Electronics |
| DCEM | Deuxième Cycle des Études Médicales | In French | → Education → Medicine |
| DCEP | Deuxième Cycle des Études Pharmaceutiques | In French | → Education → Pharmacology, toxicology |
| DCI | Dénomination Commune Internationale = INN | International Nonproprietary Name | In English = DCI | Denominación Común Internacional | In Spanish = DCI | Denominazione Comune Internazionale | In Italian = МНН | Международное непатентованное название | In Russian |
In French | → Pharmacology, toxicology |
| DCI | Denominación Común Internacional = INN, МНН (look above) |
In Spanish | → Pharmacology, toxicology |
| DCI | Denominazione Comune Internazionale = INN, МНН (look above) |
In Italian | → Pharmacology, toxicology |
| DCJT | 4-(dicyanomethylene)-2-methyl-6-(1,1,7,7-teuramethyljulolidyl-9-enyl)-4H-pyran | In English | → Chemicals |
| DCJTB | 4-(dicyanomethylene)-2-t-butyl-6(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran | In English | → Chemicals |
| DCM | Dialogue Communication Multimédia (www.dcminteractive.com) | In French | → Computer science → Graphic industries, printing, publishing |
| DCMAA | Direction Centrale du Matériel de l'Armée de l'Air | In French | → Public administration, government → Military engineering |
| DCN | Division Combustibles Nucléaires | In French | → Electrical engineering → Nuclear technology |
| DCP | Dispositifs de Concentration de Poisson | In French | → Fishing, hunting |
| DCS | Diplôme Comptable Supérieur | In French | → Specialized or (poly)technical colleges → Accounting |
| DCSD | Département Commande des Systèmes et Dynamique du vol | In French | → Electronics → Aeronautics, aircraft |
| DCSSA | Direction Centrale du Service de Santé des Armées | In French | → Public administration, government → Medicine |
| DCTB | Dansk Center for Translationel Brystkræftforskning | In Danish | → Oncology |
| DCTIM | Direction Centrale des Travaux Immobiliers Maritimes | In French | → Environmental technology, water supply, waste management → Building |
| DCU | Diplôme Comptable d'Université | In French | → Higher education, universities → Accounting |
| DDA | Direction Départementale de l'Agriculture | In French | → Public administration, government → Agricultural sciences |
| DDAF | Direction Départementale de l'Agriculture et de la Forêt | In French | → Regional administration → Agricultural sciences → Forestry |
| DDASS | Direction Départementale des Affaires Sanitaires et Sociales | In French | → Regional administration → Social welfare → Medicine |
| DDC | Defense Documentation Center | In English | → Libraries → 355 → Military engineering |
| DDD | Dense Deposit Disease | In English | → Physiology → Pathology |
| DDDS | Drug Discovery and Development Summit | In English | → Pharmacology, toxicology |
| DDE | Direction Départementale de l'Équipement | In French | → Regional administration → Civil engineering → Civil engineering and land transport |
| DDF | De Dietrich Ferroviaire | In French | → Rail transport engineering |
| DDG | Deutsche Diabetes Gesellschaft | In German | → Organizations and associations → Physiology → Pathology |
| DDP | Disc Description Protocol | In English | → Cinema, movies → Telecommunications |
| DDS | Drug Delivery System | In English | → Pharmacology, toxicology |
| DDV | Deutscher Direktmarketing Verband | In German | → Organizations and associations → 659 |
| DE | Donor Eggs | In English | → Reproductive biology |
| DE | Display Electronics | In English | → Electronics |
| DE | Deutsche Epilepsievereinigung (www.epilepsie.sh) | In German | → Organizations and associations → Neurology |
| DEA | Deployed Electronics Assembly | In English | → Electronics |
| DEA | Display Electronics Assembly | In English | → Electronics |
| DEA | Digital Electronics Assembly | In English | → Electronics |
| DEAT | Donegal Energy Action Team | In English | → Energy economics |
| DEC | Diplôme d'Expert-Comptable | In French | → Specialized or (poly)technical colleges → Accounting |
| DEC | Diplôme d'Expertise Comptable | In French | → Specialized or (poly)technical colleges → Accounting |
| DECF | Diplôme d'Études Comptables et Financières | In French | → Finance → Specialized or (poly)technical colleges → Accounting |
| DECL | Direct Energy Conversion Laboratory | In English | → Research institutes → Energy economics |
| DECT | Digital Enhanced Cordless Telecommunications | In English | → Telecommunications |
| DECT | Digital Enhanced Cordless Telecommunication | In English | → Telecommunications |
| DEEE | Déchets des équipements électriques et électroniques = WEEE | Waste Electrical and Electronic Equipment | In English |
In French | → Electrical engineering → Electronics → Environmental technology, water supply, waste management |
| DEEIT | Division de l'Électricité, de l'Électromécanique, de l'Informatique et des Télécommunications | In French | → Computer science → Electrical engineering → Electronics → 65 |
| DEFA | Dana Esperantista Fervojista Asocio | In Esperanto | → Associations → Rail transport engineering → Transport and postal services |
| DefEl | Defense Electronics | In English | → Serial publications, periodicals → 355 → Electronics → Military engineering |
| DEFF | Danmarks Elektroniske Forskningsbibliotek | In Danish | → Libraries → Electronics |
| DEFRA | Department of Environment, Food and Rural Affairs | In English | → Central administration → Agricultural sciences → Food technology |
| DEGAM | Deutsche Gesellschaft für Allgemeinmedizin und Familienmedizin | In German | → Organizations and associations → Medicine |
| DEHOMAG | DEutsche HOllerith MAschinen Gesellschaft | In German | → Mechanical engineering |
| DEI | Direction de l'Électronique et de l'Informatique | In French | → Computer science → Electronics |
| DELMIA | Digital Enterprise Lean Manufacturing Interactive Application | In English | → Computer-based techniques → Engineering, technology |
| DEMAR | Déambulation et Mouvement Artificiel | In French | → Anatomy → Mechanical engineering |
| DÉMÁSZ | Dél-magyarországi Áramszolgáltató Részvénytársaság | In Hungarian | → Energy economics → Electrical engineering |
| DEMKO | Danmarks Elektriske Materielkontrol | In Danish | → Electrical engineering |
| DENA | Deutsche Energie-Agentur | In German | → Energy economics |
| DEP | Display Electronics Package | In English | → Electronics |
| DEPT | Direction Électricité Production Transports | In French | → Electrical engineering |
| DES | Département d’Évaluation de la Sûreté | In French | → Central administration → Nuclear technology |
| DES | Drug Eluting Stent | In English | → Pharmacology, toxicology |
| DeScE | Defense Science Electronics | In English | → Serial publications, periodicals → 355 → Electronics → Military engineering |
| DESCF | Diplôme d'Études Supérieures Comptables et Financières | In French | → Finance → Specialized or (poly)technical colleges → Accounting |
| DESE | Département d’Exploitation du Système Électrique | In French | → Military engineering |
| DEST | Diplôme d'Études Supérieures Technologiques | In French | → Specialized or (poly)technical colleges → Engineering, technology |
| DESTA | Diplôme d'Études Supérieures Technologiques Approfondies | In French | → Specialized or (poly)technical colleges → Engineering, technology |
| DESTU | Diplôme d'Études Supérieures Technologiques Universitaires | In French | → Higher education, universities → Engineering, technology |
| DET | Direct Energy Transfer | In English | → Energy economics |
| DETAB | Diplôme d'État de Technicien en Analyses biomédicales | In French | → Education → Biological sciences → Medicine |