- circumnavigation
- circumscribe
- circumstances
- circumstantial evidence
- citation
- cite
- citified
- citron
- clammy
- clamorous
- clampdown
- clan
- clandestine marriage
- clapper
- claw
- clax of brass
- clay cart
- clean-cut
- clean-shaved head
- cleanse
- clergyman, clergywoman
- clerical
- clever feat
- cleverness
- clich
- clitoria
- cloaca
- clod
- 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
- come into or enter one's head
- come short of
- come thick and fast
- come under the hammer
- come up
- come up to
- comedian
- comet
- commemorative
- commercial
- common cold
- common ground
- common touch
- communicable
- communicable diseases
- comose
- companion
- compared
- comparison
- compartmentalize
- compass
- compassion
- compassionate allowance
- compatible
- cull
- compete
- competent for
- competitive
- compile duration
- complacency
- comport comport oneself
- compose oneself
- composite
- compound condition
- compoundable
- concealed
- conceive
- conciliatory
- conclusion
- conclusively proved