| Abbreviation | Definition |
|---|---|
| CCSN | core-collapse supranovæ |
| CD | Cosmic Debris |
| CDA | Cosmic Dark Ages |
| CDM | Cold Dark Matter |
| CDMH | Cold Dark Matter Halo |
| CEO | Corporate Europe Observatory |
| CES | Central Electromagnetic Shower |
| CEV | Crew Exploration Vehicle |
| CFCO | Committee For Crescent Observation |
| CFCP | Center For Cosmological Physics |
| CFS | Chandrasekhar - Friedmann - Schutz instability |
| CG | Central Galaxy |
| CGCS | Catalogue of Galactic Carbon Stars |
| CGRO | Compton Gamma Ray Obsrvatory |
| CGWA | Center for Gravitational Wave Astronomy |
| CHAMP | CAMPARE HERA Astronomy Minority Partnership |
| CHIP | Cosmic Hot Interstellar Plasma |
| CHSS | Century Halo Star Survey |
| CHZ | Circumstellar Habitable Zone |
| CIB | Cosmic Infrared Background |