| A | B |
| colloquial | conversational |
| colossal | huge |
| compatible | capable of getting along together |
| complacent | satisfied with oneself |
| concise | brief but complete |
| copious | plentiful; large in supply |
| countenance | appearance especially facial expressions; the face and its features |
| crafty | sly, clever; mentally quick |
| credible | believable |
| credulous | given to believing anything too easily |
| cumberson | bulky; awkward to deal with |
| cursory | done quickly but only on the suface |
| curt | rudely brief |
| defame | to attack a reputation through libeland slanderous acts |