- client
- clientele
- cliff
- cliffhanger
- climactic
- climate
- climate change
- climatic
- climax
- climb
- climb-down
- climber
- climbing
- climbing frame
- climes
- clinch
- cling
- clingfilm
- clinging
- clinic
- clinical
- clinically
- clink
- clip
- clipboard
- clip-on
- clipped
- clippers
- clipping
- clique
- clitoris
- cloak
- cloak-and-dagger
- cloakroom
- clobber
- clock
- clock radio
- clockwise
- clockwork
- clod
- clog
- clogged
- cloister
- cloistered
- clone
- close
- close
- close quarters
- close season
- close-cropped
- closed
- closed circuit television
- closed season
- closed shop
- closedown
- close-fitting
- close-knit
- closely
- closeness
- closeout
- closet
- close-up
- closing
- closing price
- closure
- clot
- cloth
- clothe
- clothes
- clothes basket
- clothes brush
- clothes peg
- clotheshorse
- clothesline
- clothing
- clotted cream
- cloud
- cloudburst
- cloudless
- cloudy
- clout
- clove
- clover
- clown
- cloying
- club
- club car
- clubhouse
- cluck
- clue
- clued-up
- clueless
- clump
- clumsily
- clumsy
- clung
- cluster
- clutch
- clutch bag
- clutter
- cm
- CNAA
- CND
- co-
- c/o
- CO
- CO
- Co.
- coach
- coach station
- coach trip
- coaching
- coagulate
- coal
- coal gas
- coal merchant
- coalesce
- coalface
- coalfield
- coalition
- coalman
- coalmine
- coalminer
- coalmining
- coarse
- coarse fishing
- coarsen
- coast
- coastal
- coaster
- coastguard
- coastline
- coat
- coat hanger
- coat of arms
- coat stand
- coating
- coauthor
- coax
- coaxial cable
- cob
- cobalt
- cobble
- cobbled
- cobbler
- cobbles
- Cobol
- cobra
- cobweb
- Coca-Cola®
- cocaine
- cocaine addict
- cock
- cock-a-hoop
- cockatoo
- cocker spaniel
- cockerel
- cockeyed
- cockfight
- cockle
- Cockney
- cockpit
- cockroach
- cocksure
- cocktail
- cocktail dress
- cocktail party
- cocktail shaker
- cocktail stick
- cock-up
- cocky
- cocoa
- coconut
- cocoon
- COD
- cod
- code
- code name
- code of practice
- coded
- codeine
- cod-liver oil
- codswallop
- coed
- coeducational
- coefficient
- coerce
- coercion
- coexist
- coexistence
- coffee
- coffee bar
- coffee beans
- coffee break
- coffee cup
- coffee mill
- coffee morning
- coffee shop
- coffee table
- coffee-maker