- Concupiscence
- Concur
- Concurence
- Concurrence
- Concurrent processing
- Condemnable
- Confection
- Confectionary
- Confectioner
- Confederates
- Confederation
- Conference
- Confess
- Confession
- Confessor
- Confidant
- Confidante
- Confidence
- Confident
- Configuration
- Confine
- Confined to prison
- Conniver
- Connubial
- Conquer
- Conquering
- Consecution
- Consecutive
- Consecutively
- Consent
- Consequence
- Consequent
- Conspicuous
- Constable
- Constipate
- Constipation
- Constitution
- Constitutional
- Constraint
- Constriction
- Construction
- Constructive thinking
- Consuetude
- Consul
- Consular
- Continual
- Continuance
- Continuum
- Contraception
- Contractile
- Contractile vacuole
- Contraction
- Contracture
- Contradict
- Contradiction in terms
- Contraindication
- Contrariety
- Convene
- Convener , convenor
- Convent
- Convergent
- Conversational
- Conversationalist
- Converter
- Cooling
- Coolly
- Coon
- Coop
- Cooperation
- Cooperative
- Coordinated
- Coordinator
- Copacetic
- Copasetic
- Copper
- Copper coin
- Copper-coloured
- Coppice
- Corps
- Corpse
- Corpulence
- Corpulency
- Corpulent
- Corpulent person
- Correspond
- Correspondence
- Corridor
- Corroborant
- Corrodible
- Corrody
- Cost of living
- Croaky
- Cosumed
- Cot with coir matting
- Cote
- Cotton
- Cotton cake
- Cotton on to
- Cotton wool
- Couch potato