- circuitous
- circulatory
- city-gate
- civil defence
- civil servant
- civility
- clarify
- class
- clatter
- clear statement
- clearance
- clearance sale
- clearly
- cleaving to
- cleft footed
- climate change
- cling
- clinging steadfastedly on
- clinical psychology
- close associate
- closet
- clot
- clot buster
- cloth
- clothes
- co-brother
- co-dining
- co-respondent
- coal tar
- coalesce
- cockade
- cockatoo
- cocksure
- coconut
- coconut tree
- cogent
- cognition
- cognizance
- cohort
- colicky
- collagen
- collect
- collected
- collectible
- collection
- colonist
- coloquial
- colorful
- colour brine
- colour line
- colourless
- colporteur
- combination
- come between
- come down on
- crime
- come to
- come to a head
- come to grips with, get to grips with
- come to terms
- comforting
- comfortless
- coming to blows
- command
- common cold
- common ground
- comose
- compete
- competent for
- competitive
- compile duration
- complacency
- complaisant
- complement
- completely
- complexity
- comport comport oneself
- compose oneself
- composite
- compound condition
- compoundable
- comprehend
- comprehension
- compressor
- compulsion
- compulsory
- computer
- concentrated
- concentre
- concentric
- concept
- concern
- conch-blower
- conchoidal
- conciliate
- conciliatory
- conclusion
- conclusively proved
- concoct
- condom