- Clean-cut
- Cleanse
- Clear
- Clear off
- Clear water
- Clew
- Click and drag
- Clicktivism
- Climber
- Clinch
- Clinder
- Cling
- Clipper
- Cloaca
- Cloak
- Cloistral
- Close fisted man
- Close ranks
- Close shave
- Close-mouthed
- Closed
- Closed fist
- Closely
- Closely related
- Closeness
- Closet
- Closure motion
- Clothe
- Cloud
- 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
- Codes
- Codification
- Codifier
- Codify
- Codswallop
- Coeliac
- Coenzyme
- Coercion
- Coexisting
- Coffee-table book
- Coffin
- Cogent
- Cognomen
- 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
- Colonitis
- Colony
- Colorful
- Colors
- Colossal
- Colostrums
- Colour box
- Colourist
- Colours
- Column
- Columnar
- Com
- Com and go
- Come into force
- Come on
- Come thick and fast