- cloveA very pungent aromatic spice, the unexpanded flower bud of the clove tree.
- cloyTo fill up or choke up; to stop up.
- clavicornHaving antennas shaped like clubs; used especially of the Clavicornes group of beetles
- claviformLarger at the tip than at the base; club-shaped.
- clavusA callous growth, especially on the foot; a corn.
- triclavianismThe belief that three nails were used in the crucifixion of Jesus Christ.