A four letter word beginning with C and ending with X is crux.
Coxa
chid
Cage is a four-letter word that starts with c and means cell. Or case! Or the 5 letter word Crypt!
A seven letter word beginning with C with a the fourth letter C is cracker.
Cart Colt Cram Card Cats Cite Clam Cold
cast, cost, cusp, cyst, curt, club, crib, crab
catastrophe
creamer
A remarkable person, eccentric or amusing, can be known as a 'card'
gas
circuit
Carpal Christ Cramps