Crimen, a charge; crime, criminate.
Crux (cruc-is), a cross; crucial, crucifix.
Cubo, I lie down; incubate, recumbent.
Culpa, a fault; culpable, exculpate, culprit.
Cura, care; sinecure, curate, secure, accurate.
Curro (curs-um), I run; cursory, course, recur, occur.
Decem, ten; decimal, December.
Dens (dent-is), a tooth; dentist, dental, indent.
Deus, a god; deity, deify, divine.
Dexter, right hand; dexterous.