- Closely
- Closely related
- Closeness
- Closet
- Closure motion
- Clothe
- Cloud
- Cloudily
- Cloudiness
- Cloudscape
- Clowder
- Clown
- Cloying
- Clump
- Cluster of lotus blossoms
- Cm
- Cml
- Co-belligerent
- Co-dining
- Co-owner
- Co-traveller
- Coadjutor
- Coagulated
- Coagulation
- Coal
- Coal gas
- Coalescence
- Coalface
- Coalite
- Coalition
- Coat hanger
- Coaxing
- Cob
- Cobweb
- Cobwebs
- Cock and bull story
- Cock eye
- Cock-a-hoop
- Cock-crest
- Cockatoo
- Cockerel
- Cockernony
- Cockle
- Cocky
- Cocoa
- Coconut leaves
- Coconut oil
- Coconut palm
- Coconut toddy
- Cod
- Coddiwomple
- Codes
- Codification
- Codifier
- Codify
- Codswallop
- Coeliac
- Coenzyme
- Coercion
- Coexisting
- Coffee-table book
- Coffin
- Cogent
- Cognomen
- Coherence
- Coherent
- Coherently
- Cohesion
- Coiffure
- Coinage
- Coincide
- Coincidence
- Coincidental
- Coir fibre
- Coital
- Coitus
- Colander
- Cold
- Cold comfort
- Cold turkey
- Cold water
- Coldish
- Collaborate
- Collaborative
- Collar bone
- Collate
- Collation
- Colleague
- Collectible
- Collecting
- Collection of a part of produce as tax
- Collective
- Collectivize
- Collegial
- Collide
- Collie
- Collinear
- Colloquial usage
- Colloquy
- Collywobbles