

| Acronym | Sense | Language | Topics | 
|---|---|---|---|
| CERHIC | Centre d'Études et de Recherche en Histoire Culturelle | In French | → Research institutes → History → Civilization, culture, progress | 
| CERIB | Centre d'Études et de Recherches de l'Industrie du Béton | In French | → Research institutes → Civil engineering → Construction | 
| CERMO | Centre d'Études et de Recherches de la Machine-Outil | In French | → Research institutes → Mechanical engineering | 
| CERP | Comité Européen de Réglementation Postale | In French | → Standardization → Postal services → Europe | 
| CERSA | Centre d'Études et de Recherches de Sciences Administratives | In French | → Research institutes → Public administration, government | 
| CERT | Centre d'Études et de Recherche de Toulouse | In French | → Research institutes | 
| CERT | Center for Education Resources and Technology | In English | → Research institutes → Education | 
| CERTU | Centre d'Études sur les Réseaux, les Transports, l'Urbanisme et les constructions publiques | In French | → Research institutes → Civil engineering → Transport and postal services → Construction | 
| CES | Confédération Européenne des Syndicats (www.etuc.org) = ETUC | European Trade Union Confederation | In English = CES | Confederación Europea de Sindicatos | In Spanish = EVV | Europees Verbond van Vakverenigingen | In Dutch | In French | → Labour, labour economics | 
| CES | Confederación Europea de Sindicatos (www.etuc.org) = ETUC, EVV (look above) | In Spanish | → Labour, labour economics | 
| CESA | Canadian Engineering Standards Association | In English | → Associations → Standardization → Engineering, technology → Canada | 
| CESCM | Centre d'Études Supérieures de Civilisation Médiévale (www.mshs.univ-poitiers.fr/cescm) | In French | → Research institutes → History | 
| CESCM | Centre d’Études Supérieures de Civilisation Médiévale | In French | → Research institutes → History | 
| CESI | Confédération Européenne des Syndicats Indépendants = CESI | Confederación Europea de Sindicatos Independientes | In Spanish | In French | → Labour, labour economics → Europe | 
| CESI | Confederación Europea de Sindicatos Independientes = (look above) | In Spanish | → Labour, labour economics → Europe | 
| CESL | Confederación Europea de Sindicatos Libres | In Spanish | → Labour, labour economics | 
| CESML | Coopérative d'Électricité de Saint-Martin de Londres (http://https://cesml.com) | In French | → Electrical engineering → France | 
| CESO | Canadian Executive Service Organization = SACO | Service d'Assistance Canadienne aux Organismes | In French | In English | → Development → Canada | 
| CESS | Central Eurasian Studies Society (www.cess.muohio.edu) | In English | → Area studies | 
| CESTAS | Centro di Educazione Sanitaria e Tecnologie Appropriate Sanitarie | In Italian | → Medicine | 
| CESVI | Cooperazione e Sviluppo | In Italian | → Development | 
| CETEA | Centro de Tecnologia de Embalagem | In Portuguese | → Research institutes | 
| CETEM | Centro de Tecnologia Mineral (www.cetem.gov.br) | In Portuguese | → Research institutes → Mining → Brazil | 
| CETIOM | Centre Technique Interprofessionnel des Oléagineux Métropolitains | In French | → Research institutes → Agricultural sciences | 
| CETR | Corpul Expertilor Tehnici din România | In Romanian | → Applied sciences, technology → Romania | 
| CETU | Centre d'Études des Tunnels | In French | → Research institutes → Civil engineering | 
| CEVI | Confédération Européenne des Vignerons Indépendants | In French | → Agricultural sciences → Beverage industry → Europe | 
| CEVI | Centro di Volontariato Internazionale | In Italian | |
| CEVO | Compascumer Erfscheidense Voetbal en Ontspanningsvereniging | In Dutch | → Football and rugby → Netherlands | 
| CEVU | Conseil des Études et de la Vie Universitaire | In French | → Higher education, universities | 
| CEWC | Council for Education in World Citizenship | In English | → Education | 
| CfA | Harvard-Smithsonian Center for Astrophysics (https://www.cfa.harvard.edu/) | In English | → Research institutes → Astronomy → United States | 
| CFA | Canadian Flag Association | In English | → Associations → Flags, banners → Canada | 
| CFA | Cat Fancier's Association (www.cfa.org) | In English | → Associations | 
| CFA | Comité Français des Aérosols | In French | → Chemical technology | 
| CFAR | Collège Français des Anesthésistes Réanimateurs | In French | → Anesthesiology → France | 
| CFAR | Center for Functional Assessment Research | In English | → Research institutes | 
| CFBMC | Canadian Farm Business Management Council = CCGEA | Conseil Canadien de la Gestion d'Entreprise Agricole | In French | In English | → Economics → Agricultural sciences | 
| CFBR | Comité Français des Barrages et Réservoirs | In French | → Civil engineering → 626 → France | 
| CFC | Community Foundations of Canada (www.cfc-fcc.ca) = FCC | Fondations Communautaires du Canada | In French | In English | → Foundations → Canada | 
| CFCC | Comité Français de Coordination du Carburéacteur | In French | → Aeronautics, aircraft → France | 
| CFCG | Confédération Française du Commerce de Gros | In French | → Trade → France | 
| CFCM | Conseil Français du Culte Musulman | In French | → Islam → France | 
| CFCV | Collectif féministe contre le viol | In French | → Feminism | 
| CFDT | Confédération Française des Travailleurs | In French | → Labour, labour economics → France | 
| CFDT | Confédération Française Démocratique du Travail (www.cfdt.fr) | In French | → Labour, labour economics → France | 
| CFE | Commission Fédérale des Étrangers | In French | → Migrations | 
| CFE | Conseil de la Famille et de l'Enfance | In French | → Social welfare | 
| CFE | Comisión Federal de Electricidad | In Spanish | → Central administration → Electrical engineering | 
| CFE-CGC | Confédération Française de l'Encadrement - Confédération Générale des Cadres (www.cfecgc.org) | In French | → Management → Labour, labour economics → France | 
| CFEP | Chambre des Fonctionnaires et Employés Publics | In French | → Labour, labour economics → Public administration, government | 
| CFGB | Comité Français des Grands Barrages | In French | → Civil engineering → 626 | 
| CFH | Conference on Faith and History | In English | → Religion, theology → History | 
| CFI | Chemisches Forschungsinstitut der Wirtschaft Österreichs | In German | → Research institutes → Chemistry → Chemical technology → Austria | 
| CFI | Center for Inquiry | In English | → Philosophy, psychology | 
| CFIDC | China Football Industry Development Corporation | In English | → Football and rugby → China | 
| CFMN | Centre de Fabrication Mécanique pour la Neurophysiologie | In French | → Research institutes → Mechanical engineering → Physiology → Neurology | 
| CFMN | Comunità dei Figli di Maria di Nazaret | In Italian | → Christianity | 
| CFMN | Comisión Femenil Mexicana Nacional | In Spanish | → Feminism → Mexico | 
| CFN | Conselho Federal de Nutricionistas | In Portuguese | → Nutrition | 
| CFPB | Consortium Français de Participations Bancaires | In French | → Banks → France | 
| CFQ | Confédération Française de la Quincaillerie | In French | → Trade → France | 
| CFR | Colegiul Farmacistilor din România | In Romanian | → Pharmacology, toxicology → Romania | 
| CFTC | Confédération Française des Travailleurs Chrétiens (www.cftc.fr) | In French | → Labour, labour economics → Christianity → France | 
| CFU | Comité Français UNIMARC | In French | → Documentation → Libraries → France | 
| CFZ | Centrum Flagi Ziemi | In Polish | → Flags, banners | 
| CGA | Confédération Générale de l'Agriculture | In French | → Agricultural sciences → History → France | 
| CGA | Cercle Généalogique d'Alsace | In French | → Genealogy | 
| CGA | Compressed Gas Association (www.cganet.com) | In English | → Associations → Chemical technology | 
| CGA | Casual Games Association (www.casualgamesassociation.org) | In English | → Associations → Software → Entertainment | 
| CGAM | Centre for Global Atmospheric Modelling (www.cgam.nerc.ac.uk) | In English | → Research institutes → Meteorology, climatology → United Kingdom | 
| CGB | Christlicher Gewerkschaftsbund | In German | → Christianity → Labour, labour economics | 
| CGB | Confédération Générale des planteurs de Betteraves (www.cgb-france.fr) | In French | → Agricultural sciences → France | 
| CGC | Confédération Générale des Cadres | In French | → Labour, labour economics | 
| CGCEH | Conference Group for Central European History | In English | → History → Area studies | 
| CGDI | Consejo General de los colegios oficiales de Decoradores Diseñadores de Interior | In Spanish | → Architecture | 
| CGE | Conférence des Grandes Écoles | In French | → Specialized or polytechnical colleges | 
| CGFL | Centre Georges-François Leclerc | In French | → Oncology | 
| CGIAR | Consultative Group on International Agricultural Research | In English | → Research policy → Agricultural sciences | 
| CGMP | Cercle Généalogique de Maine et Perche | In French | → Genealogy | 
| CGMP | Centre Généalogique du Midi-Provence (www.cgmp-provence.org) | In French | → Genealogy | 
| CGPME | Confédération Générale des Petites et Moyennes Entreprises | In French | → Labour, labour economics | 
| CGPT | Confédération Générale des Travailleurs Paysans | In French | → Labour, labour economics → Agricultural sciences | 
| CGS | Cinecircoli Giovanili Socioculturali | In Italian | |
| CGSAH | Conference Group for Social and Administrative History | In English | → Sociology → Public administration, government → History | 
| CGSESE | Centre de Gestion de la Sécheresse pour l'Europe du Sud-Est = DMCSEE | Drought Management Centre for South-Eastern Europe | In English | In French | → Natural disasters → Europe | 
| CGSLB | Centrale Générale des Syndicats Libéraux de Belgique = ACLVB | Algemene Centrale der Liberale Vakbonden | In Dutch | In French | → Labour, labour economics → Belgium | 
| CGT | Confédération Générale du Travail | In French | → Labour, labour economics | 
| CGT | Confédération Générale des Travailleurs | In French | → Labour, labour economics | 
| CGT-FO | Confédération Générale du Travail-Force Ouvrière | In French | → Labour, labour economics | 
| CGT-FO | Confédération Générale des Travailleurs - Force Ouvrière | In French | → Labour, labour economics | 
| CGT-SR | Confédération Générale du Travail Syndicaliste Révolutionnaire | In French | → Labour, labour economics | 
| CGTL | Confédération Générale du Travail Luxembourgeoise | In French | → Labour, labour economics → Luxembourg | 
| CGTL | Confédération Générale des Travailleurs du Liban | In French | → Labour, labour economics | 
| CGTP | Confederação Geral dos Trabalhadores Portugueses (www.cgtp.pt) | In Portuguese | → Labour, labour economics → Portugal | 
| CGTU | Confédération Générale du Travail Unitaire | In French | → Labour, labour economics → History | 
| CGU | Canadian Geophysical Union (www.cgu-ugc.ca) = UGC | Union Géophysique Canadienne | In French | In English | → Geophysics → Canada | 
| CH&D | Center for Hearing and Deafness | In English | → Research institutes → Pathology | 
| CHA | Canadian Historical Association = SHC | Société Historique du Canada | In French | In English | → Associations → History → Canada | 
| CHA | Canadian Hockey Association (www.hockeycanada.ca) | In English | → Associations → Sport, physical exercises → Canada | 
| CHA | Caribbean Hotel Association | In English | → Associations → Tourism | 
| CHA | Certified Horsemanship Association | In English | → Associations → Sport, physical exercises | 
| CHA | Craft and Hobby Association | In English | → Associations | 
| CHA | Catholic Health Association | In English | → Associations → Roman catholic church → Medicine | 
| CHAR | Centre d'Histoire de l'Art de la Renaissance | In French | → Research institutes → Arts → History | 
| CHARTH | Compagnie Holding d'Applications et de Réalisations Thermiques et Hydrauliques | In French | → Energy economics → Mechanical engineering | 
| CHAVI | Center for HIV-AIDS Vaccine Immunology | In English | → Research institutes → Immunology and allergy → Infectious diseases | 
| CHC | Czechoslovak History Conference | In English | → History | 
| CHEAM | Centre des Hautes Études sur l'Afrique et l'Asie modernes | In French | → Research institutes → Area studies | 
| CHEAr | Centre des Hautes Études de l'Armement | In French | → Research institutes → Military engineering | 
| CHHS | Charles Homer Haskins Society | In English | → History | 
| CHJ | Conference of Historical Journals | In English | → Serial publications, periodicals → History | 
| CHLA | Canadian Health Libraries Association = ABSC | Association des Bibliothèques de la Santé du Canada | In French | In English | → Libraries → Associations → Medicine → Canada | 
| CHRC | Cito - Harten Rijn Combinatie | In Dutch | → Sport, physical exercises | 
| CHUS | Chinese Historians in the United States | In English | → History → United States | 
| CIA | Centre International des Alliances | In French | → Christianity | 
| CIAM | Congrès International d'Architecture Moderne | In French | → Architecture | 
| CIBT | Conseil International des Bois Tropicaux | In French | → Timber and woodworking industry | 
| CIC | Centre d'Investigation Clinique | In French | → Pharmacology, toxicology | 
| CIC | Centro Internazionale Crocevia | In Italian | |
| CIC | Conseil International des Céréales | In French | → Agricultural sciences | 
| CICA | Centre International du Cinéma d'Animation | In French | → Cinema, movies | 
| CICAE | Confédération Internationale des Cinémas d'Art et d'Essai (www.cicae.org) | In French | → Cinema, movies | 
| CICESE | Centro de Investigación Científica y de Educación Superior de Ensenada (www.cicese.mx) | In Spanish | → Research institutes → Research policy → Higher education, universities → Mexico | 
| CICF | Confédération des Industries Céramiques de France | In French | → 666 → France | 
| CICF | Chambre des Ingénieurs-Conseil de France | In French | → Engineering, technology → France | 
| CICI | Commission Internationale de Coopération Intellectuelle | In French | → International relations | 
| CICLIM | Coordination Internationale des Chercheurs sur les Littératures du Maghreb | In French | → Literature | 
| CICP | Cambodian Institute for Cooperation and Peace (www.cicp.org.kh) | In English | → Research institutes → Democracy → Internal policy → International relations | 
| CICR | Comité Internacional de la Cruz Roja (www.icrc.org) = ICRC | International Committee of the Red Cross | In English = CICR | Comité International de la Croix-Rouge | In French = CICV | Comitê Internacional da Cruz Vermelha | In Portuguese = МККК | Международный комитет Красного Креста | In Russian = SSKK | Starptautiskā Sarkanā Krusta Komiteja | In Latvian = CICR | Comitato Internazionale della Croce Rossa | In Italian = ICRC | 적십자 국제 위원회 | In Korean = CICR | Comitè Internacional de la Creu Roja | In Catalan = CICR | Comitât entèrnacionâl de la Crouèx-Roge | In Franco-Provençal | In Spanish | → Medicine | 
| CICR | Comité International de la Croix-Rouge (www.icrc.org) = ICRC, CICV, МККК, SSKK (look above) | In French | → Medicine | 
| CICR | Comitato Internazionale della Croce Rossa (www.icrc.org) = ICRC, CICV, МККК, SSKK (look above) | In Italian | → Medicine | 
| CICR | Comitè Internacional de la Creu Roja (www.icrc.org) = ICRC, CICV, МККК, SSKK (look above) | In Catalan | → Medicine | 
| CICR | Comitât entèrnacionâl de la Crouèx-Roge (www.icrc.org) = ICRC, CICV, МККК, SSKK (look above) | In Franco-Provençal | → Medicine | 
| CICTA | Commission Internationale pour la Conservation des Thonidés de l'Atlantique et des mers adjacentes | In French | → Environmental protection → Fishing, hunting | 
| CICTE | Comisión Interamericana contra el Terrorismo = CICTE | Comitê Interamericano de Combate ao Terrorismo | In Portuguese | In Spanish | → Polemology | 
| CICTE | Comitê Interamericano de Combate ao Terrorismo = (look above) | In Portuguese | → Polemology | 
| CICV | Comitê Internacional da Cruz Vermelha (www.icrc.org) = CICR, ICRC, МККК, SSKK (look above) | In Portuguese | → Medicine | 
| CIDA | Confederazione Italiana Dirigenti d'Azienda | In Italian | → Labour, labour economics → Italia | 
| CIDA | Comité International de Défense Anarchiste | In French | → Anarchist organizations | 
| CIDEC | Centro Interdisciplinario de Estudios Culturales | In Spanish | → Research institutes → Civilization, culture, progress | 
| CIDH | Comisión Interamericana de Derechos Humanos | In Spanish | → Human rights | 
| CIDI | Consejo Interamericano para el Desarrollo Integral = CIDI | Conseil interaméricain pour le Développement Intégré | In French = CIDI | Conselho Interamericano para o Desenvolvimento Integral | In Portuguese | In Spanish | → International relations → Development | 
| CIDI | Conseil interaméricain pour le Développement Intégré = (look above) | In French | → International relations → Development | 
| CIDI | Conselho Interamericano para o Desenvolvimento Integral = (look above) | In Portuguese | → International relations → Development | 
| CIDIS | Centro di Informazione, Documentazione e Iniziativa per lo Sviluppo | In Italian | → Libraries → Development | 
| CIDPDD | Centre International des Droits de la Personne et du Développement Démocratique (www.ichrdd.ca) = ICHRDD | International Centre for Human Rights and Democratic Development | In English | In French | → Fundamental rights → Democracy → Canada | 
| CIDS | Comisión Interamericana de Desarrollo Sostenible = CIDS | Commission Interaméricaine pour le Développement Durable | In French = CIDS | Comissão Interamericana de Desenvolvimento Sustentável | In Portuguese | In Spanish | → International relations → Development | 
| CIDS | Commission Interaméricaine pour le Développement Durable = (look above) | In French | → International relations → Development | 
| CIDS | Comissão Interamericana de Desenvolvimento Sustentável = (look above) | In Portuguese | → International relations → Development | 
| CIDST | Comité de l’Information Scientifique et Technique des Communautés Européennes | In French | → Documentation → European Union | 
| CIDUNATI | Confédération Intersyndicale de Défense et d'Union Nationale des Travailleurs Indépendants | In French | → Labour, labour economics | 
| CIE | Conférence Islamique Européenne | In French | → Islam → Europe | 
| CIELT | Centre International d'Études sur le Linceul de Turin | In French | → Roman catholic church | 
| CIES | Centro Informazione ed Educazione allo Sviluppo | In Italian | → Education → Development | 
| CIESIN | Center for International Earth Science Information Network | In English | → Research institutes → Earth sciences | 
| CIESM | Commission Internationale pour l'Exploration Scientifique de la mer Méditerranée | In French | → Marine research, oceanography | 
| CIESS | Centro Interamericano de Estudios de Seguridad Social = CIESS | Centro Interamericano de Estudos sobre Segurança Social | In Portuguese | In Spanish | → Insurance | 
| CIESS | Centro Interamericano de Estudos sobre Segurança Social = (look above) | In Portuguese | → Insurance | 
| CIF | Commission Interaméricaine des Femmes (www.oas.org/cim/) = CIM | Comisión Interamericana de Mujeres | In English = IACW | Inter-American Commission of Women | In English = CIM | Comissão Interamericana de Mulheres | In Portuguese | In French | → Feminism | 
| CIFA | Committee for Inland Fisheries of Africa | In English | → Fishing, hunting → Africa | 
| CIG | Confederación Intersindical Galega | In Spanish | → Labour, labour economics | 
| CIGOS | Canadian Interest Group on Open Systems | In English | → Software → Canada | 
| CIGRE | Conférence Internationale des Grands Réseaux Électriques à haute tension | In French | → Electrical engineering | 
| CIGREF | Club Informatique des Grandes Entreprises Françaises (www.cigref.fr) | In French | → Computer science → France | 
| CIHAM | Centre Interuniversitaire d'Histoire et d'Archéologie Médiévales | In French | → Research institutes → Archeology → History | 
| CIHEAM | Centre International des Hautes Études Agronomiques Méditerranéennes (www.ciheam.org) | In French | → Research institutes → Agricultural sciences | 
| CIHEF | Commission Internationale Humanitaire d'Établisssement des Faits (www.ihffc.org) = IHFCC | International Humanitarian Fact-Finding Commission | In English | In French | → International law | 
| CIHR | Canadian Institutes of Health Research (www.cihr.ca) = IRSC | Instituts de recherche en santé du Canada | In French | In English | → Research institutes → Biological sciences → Medicine → Canada | 
| CIID | Commission Internationale pour les Irrigations et le Drainage = ICID | International Commission for Irrigation and Drainage | In English | In French | → 627 → Agricultural sciences | 
| CIIT | Chemical Industry Institute of Toxicology | In English | → Research institutes → Pharmacology, toxicology → Chemical technology | 
| CIJEF | Conseil International des organisations de Jeunes de la Francophonie | In French | |
| CIJV | Centre International Jules-Verne (www.cijv.fr) | In French | → Museums → Literature → France | 
| CIKM | Conference on Information and Knowledge Management | In English | → Congresses → Knowledge management | 
| CIKTN | Chemistry Innovation Knowledge Transfer Network | In English | → Chemistry | 
| CILT | Center for Information on Language Teaching and Research (www.cilt.org.uk) | In English | → Education → Language, linguistics, literature → United Kingdom | 
| CIM | Comisión Interamericana de Mujeres (www.oas.org/cim/) = CIF, IACW (look above) | In English | → Feminism | 
| CIM | Comissão Interamericana de Mulheres (www.convenioandresbello.org) = CIF, IACW (look above) | In Portuguese | → Feminism | 
| CIM | Centre International de Musicothérapie | In French | → Music | 
| CIMAC | Conseil International des Machines à Combustion | In French | → Mechanical engineering | 
| CIMADE | Comité Inter-Mouvements Auprès Des Évacués | In French | → Migrations | 
| CIME | Comité d'Information et de Mobilisation pour l'Emploi | In French | → Labour, labour economics | 
| CIMLS | Cercle Informatique Médicale entre Lesse et Semois | In French | → Computer science → Medicine | 
| CIMP | Commision Internationale de Microflore Paléozoique | In English | → Paleobotany, palynology → Botany | 
| CIMR | Cambridge Institute for Medical Research (https://www.cimr.cam.ac.uk) | In English | → Research institutes → Medicine → United Kingdom | 
| CIN | Conferencia Internacional sobre Nutrición = ICN | International Conference on Nutrition | In English = CIN | Conférence Internationale sur la Nutrition | In French = CIN | Conferência Internacional sobre Nutrição | In Portuguese | In Spanish | → Congresses → Nutrition | 
| CIN | Conférence Internationale sur la Nutrition = ICN (look above) | In French | → Congresses → Nutrition | 
| CIN | Conferência Internacional sobre Nutrição = ICN (look above) | In Portuguese | → Congresses → Nutrition | 
| CINVESTAV | Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (www.cinvestav.mx) | In Spanish | → Research institutes → Specialized or polytechnical colleges → Mexico | 
| CIO | Comité International Olympique (www.olympic.org) = IOC | International Olympic Committee | In English = МОК | Международен олимпийски комитет | In Bulgarian = MOO | Međunarodni olimpijski odbor | In Bosnian = COI | Comitè Olímpic Internacional | In Catalan = MOV | Mezinárodní olympijský výbor | In Czech = IOK | Internationales Olympisches Komitee | In German = ΔΟΕ | Διεθνής Ολυμπιακή Επιτροπή | In Greek = IOK | Internacia Olimpika Komitato | In Esperanto = COI | Comité Olímpico Internacional | In Spanish = ROK | Rahvusvaheline Olümpiakomitee | In Estonian = KOK | Kansainvälinen olympiakomitea | In Finnish = COI | Comité Olímpico Internacional | In Galician = MOO | Međunarodni olimpijski odbor | In Croatian = NOB | Nemzetközi Olimpiai Bizottság | In Hungarian = TOK | Tarptautinis olimpinis komitetas | In Lithuanian = IOC | Internationaal Olympisch Comité | In Dutch = IOK | (Den) internasjonale olympiske komité | In Norwegian = MKOI | Międzynarodowy Komitet Olimpijski | In Polish = COI | Comité Olímpico Internacional | In Portuguese = МОК | Международный олимпийский комитет | In Russian = MOK | Međunarodni olimpijski komitet | In Serbo-Croatian = MOV | Medzinárodný olympijský výbor | In Slovak = MOK | Mednarodni olimpijski komite | In Slovenian = МОК | Међународни олимпијски комитет | In Serbian = IOK | Internationella Olympiska Kommitté | In Swedish = МОК | Міжнародний олімпійський комітет | In Ukrainian | In French | → Sport, physical exercises | 
| CIO | Congress of Industrial Organizations | In English | → Labour, labour economics | 
| CION | Chevron Is Onze Naam | In Dutch | → Sport, physical exercises | 
| CIOSL | Confederación Internacional de Organizaciones Sindicales Libres (www.icftu.org) = CISL | Confédération Internationale des Syndicats Libres | In French = ICFTU | International Confederation of Free Trade Unions | In English = CIOSL | Confederação Internacional de Organizações Sindicais Livres | In Portuguese = ICB | International Criminal Bar | In English = BPI | Barreau Pénal International | In French | In Spanish | → Labour, labour economics | 
| CIOSL | Confederação Internacional de Organizações Sindicais Livres (www.icftu.org) = CISL, ICFTU, ICB, BPI (look above) | In Portuguese | → Labour, labour economics | 
| CIP | Comité International Paralympique (https://www.paralympic.org/) | In French | → Sport, physical exercises | 
| CIPFG | Coalition d'Investigation sur la Persécution du Falun Gong en Chine | In French | → Modern spiritual movements | 
| CIPUF | Carrefour International de la Presse Universitaire Francophone (www.cipuf.org) | In French | → Newspapers, journalism → Higher education, universities | 
| CIRA | Centre International de Recherches sur l'Anarchisme | In French | → Research institutes → Anarchist organizations | 
| CIRASTI | Collectif Interassociatif pour la Réalisation d'Activités Scientifiques et Techniques Internationales | In French | → International relations → Applied sciences, technology → Engineering, technology | 
| CIRDN | Comité Interamericano para la Reducción de los Desastres Naturales = IACNDR | Inter-American Committee on Natural Disaster Reduction | In English = CIRDN | Comitê Interamericano sobre a Redução de Desastres Naturais | In Portuguese | In Spanish | → Natural disasters |