| Abbreviation | Definition |
|---|---|
| CIS | Cut It Short |
| CL | Call |
| CLOTHES | Curriculum Learning On Technology Have Educational Sentences |
| CMB | Call me back |
| CMI | Cannot Make It |
| CMIIW | Correct Me If I'm Wrong |
| CMON | Come On |
| C'MON | Come On |
| cnh | can Not Host |
| CNH | cannot host |
| COA | Center Of Attention |
| COF | Cough |
| CONEXS | Connections |
| COS | Because |
| Coz | Because |
| CR8 | Create |
| CRAT | Can't Remember A Time |
| CRM | Can't Remember Meaning |
| CRS | Can't Remember Stuff |
| CRZY | Crazy |