| cohesive | Condition of sticking together | |
| coherence | The quality of being logical and consistent | |
| cognizant | Having knowledge or being aware of | |
| coeval | Having the same age or date of origin; contemporary. | |
| coddle | Treat in an indulgent or overprotective way | |
| cocksure | presumptuously or arrogantly confident | |
| coalesce | To come together and form one mass or whole | |
| cloying | Disgust or sicken (someone) with an excess of sweetness, richness, or sentiment | |
| clemency | Mercy or leniency granted to an offender by a person in authority | |
| clangorous | Making a loud, resonant sound | |