- Clerodenron syphananthus
- Clever
- Clip-art
- Clip-on
- Clobber
- Clogged
- Cloistered
- Close associate
- Close cropped
- Close friend
- Close investigation
- Close over
- Clouded
- Cloudless
- Clout
- Clouted
- Clover
- Cloverleaf
- Clumsiness
- Clung
- Clunky
- Cluster
- Clustered
- Clutches
- Coarse paper
- Coarticulation
- Coastguard
- Coat
- Coating
- Coax
- Cobalt
- Cocercion
- Cochineal
- Cohabit
- Codes of morality
- Codicil
- Coerce
- Coexist
- Coffee bean
- Coffee shop
- Cognitive behavioural therapy
- Cold snap
- Cold sweat
- Cold wave
- Cole
- Colicky
- Collaboration
- Collaborators
- Collar
- Collateral damage
- Collected
- Colonisation
- Colonise
- Colonist
- Colonnade
- Coloquial
- Color
- Coloring
- Colossus
- Colour blind
- Colour brine
- Colour line
- Colourfully
- Combat
- Combatant
- Combatants
- Combe
- Combination
- Combination of syllables
- Combine
- Combustible
- Come between
- Come down with
- Come for
- Come home to roost
- Coming near
- Commander
- Commendableness
- Commensurate
- Commentator
- Commercialize
- Commission agent
- Committee
- Common multiple
- Common parlance
- Comparable
- Compass
- Compatibility
- Compatibleness, compatibility
- Compere
- Compete
- Competent for
- Complicity
- Complimentary
- Comply
- Composed of 8th part
- Compositor
- Compound
- Compound condition
- Compound sentence