- Civil behaviour
- Civil defence
- Civil liberty
- Civil servant
- Claret
- Clarified butter
- Clarinet
- Clarinettist
- Class
- Classicist
- Classics
- Classification
- Clay modelling
- Clean
- Clean out
- Cleaner
- Cleaning
- Cleansed
- Clear away
- Clear data
- Clear out
- Clear the place
- Clear the way
- Clear up
- Clear-cut
- Clearing
- Clearing station
- Cleat
- Cleavable
- Cleavage
- Cleaving to
- Cleft
- Clemency
- Clepsydra
- Clergy
- Clergyman
- Cleric
- Clerodenron syphananthus
- Clever
- Clip-art
- Clip-on
- Clobber
- Clogged
- Cloistered
- Close associate
- Close cropped
- Close friend
- Close investigation
- Close over
- Close rank
- Close round
- Close to
- Close-fitting
- Closed place
- Closefisted
- Closely built
- Closet genius
- Closing as flowers
- Clot
- Cloth purse
- Clothline
- Cncoction
- Co-axial
- Coarse
- Co-factor
- Co-operator
- Co-sister
- Coachman
- Coagulant
- Coal bed
- Coal tar
- Coarse paper
- Coarticulation
- Coastguard
- Coat
- Coating
- Coax
- Cobalt
- Cocercion
- Cochineal
- Cohabit
- Codes of morality
- Codicil
- Coerce
- Coexist
- Coffee bean
- Coffee shop
- Cognitive behavioural therapy
- Coif
- Coiled
- Coir-mats
- Cold chisel
- Cold cream
- Cold feet
- Cold frame
- Collective farm
- Collectivist
- Colleen
- Collieries
- Colliery