| Abbreviation | Definition |
|---|---|
| CINP | International College of Neuropsychopharmacology |
| CIO | Commision Internationale d'Optique |
| CIO | International Commission for Optics |
| CIOS | Channel Islands Occupation Society |
| CIP | Colegio de Ingenieros del Per |
| CIP | Colegio de Ingenieros del Perú |
| CIP | College of Engineers of Peru |
| CIPA | Comit International de Photogrammtrie Architecturale |
| CIPA | Comité International de Photogrammétrie Architecturale |
| CIPA | International Committee for Architectural Photogrammetry |
| CIPHI | Canadian Institute of Public Health Inspectors |
| CIPL | Comit International Permanent des Linguistes |
| CIPL | Comité International Permanent des Linguistes |
| CIPL | Permanent International Committee of Linguists |
| CIPS | Association Canadienne de l'Informatique |
| CIPS | Canadian Information Processing Society |
| CIPSH | Conseil International de la Philosophie et des Sciences Humaines |
| CIPSH | International Council for Philosophy and Humanistic Studies |
| CIRSE | Cardiovascular and Interventional Radiological Society of Europe |
| CIS | Center for Internet and Society |