| CAA | Civil Aviation Authority |
| CABE | Central Advisory Board of Education |
| CAG | Comptroller and Auditor General |
| CAPES | Computer-Aided Paperless Examination System |
| CAZRI | Central Arid Zone Research Institute |
| CBI | Central Bureau of Investigation |
| CECA | Comprehensive Economic Cooperation Agreement |
| CFC | Chlorofluoro Carbon |
| CID | Criminal Investigation Department |
| CISF | Central Industrial Security Force |
| CITES | Convention on International Trade in Endangered Species |
| CNG | Compressed Natural Gas |
| COFEPOSA | Conservation of Foreign Exchange and Prevention of Smuggling Act |
| CPCB | Central Pollution Control Board |
| CPRI | Central Power Research Institute |
| CRR | Cash Reserve Ratio |
| CSIR | Council of Scientific and Industrial Research |
| DAVP | Directorate of Advertising and Visual Publicity |
| DDT | Dichloro-Dlphenyl Trichloro-ethane (disinfectant) |
| DNA | De-oxyribonuclelc Acid |
| DPSA | Deep Penetration Strike Aircraft |
| DPT | Diphteria, Pertussis and Tetanus |
| DRDO | Defence Research and Development Organisation |
| DTH | Direct-to-Home (broadcasting) |
| DVD | Digital Versatile Disk |
| ECG | Electro Cardiogram |
| EEG | Electro-Encephalography |
| EET | Exempt Exempt Taxation |
| ESCAP | Economic and Social Commission for Asia and the Pacific |
| EVM | Electronic Voting Machine |