- calm
- calomel
- calorie
- calumniation
- calvary
- curtsy
- curvilinear regression
- cuspidor
- cuspidate
- cussedness
- custom
- cuticle
- cutis
- cutpurse
- cutting edge
- cut down
- cymbal
- cynodon dactylon
- cryosurgery
- craniotomy
- cautery
- cognitive process
- cognitive operation
- caress
- cricket
- caper
- cuckold
- circumvent
- Chloromycetin
- Cistus
- capitalise
- Canis familiaris
- courser
- crucial
- coetaneous
- croton
- castor bean plant
- currant
- Camellia sinensis
- cotton plant
- carissa
- cedar
- cochineal
- crane fly
- craziness
- cocktail
- concatenation
- coquetry
- cervid
- casualty