| Abbreviation | Definition |
|---|---|
| CED | Capacitance Electronic Disc |
| CEN | Chemical and Engineering News |
| CEN | Chemical Engineering News |
| CENS | China Economic News Service |
| CES | Consumer Electronics Show |
| CFA | Communauté Francophone en Afrique |
| CFIS | Corona Fundamental Intermediate School |
| CGMS-A | Copy Generation Management SystemAnalog |
| CGMS-A | Copy Generation Management System—Analog |
| CHAIN | Communication Help Advise Information And News |
| CHNN | Collision Hub News Network |
| CIMG | Creative Ice Media Group |
| CIN | Chemical Industry Notes |
| CIRT | Camera Nacional de la Indústria de Radio y Televisión ( Mexico) |
| CJN | Cleveland Jewish News |
| CLAMS | College Librarians and Media Specialists |
| CLAY | Clowns Laughing At You |
| CLN | Continuous Learning News |
| CLT | Compagnie Luxembourgeoise de Télédiffusion |
| CM | Cassette Module |