Webster's New World Medical Dictionary

CPAP
Continuous positive airway pressure. See
also 
sleep apnea.
CPR
Cardiopulmonary resuscitation.
crabs
Slang for pubic lice, parasitic insects that
can infest in the genital area of humans. Pubic lice
are usually spread through sexual contact. Rarely,
infestation can be spread through contact with an
infested person’s bed linens, towels, or clothes. The
key symptom of pubic lice is itching in the genital
area. Lice eggs (nits) or crawling lice can be seen
with the naked eye.
cracked-tooth syndrome
A toothache caused
by a broken tooth (tooth fracture), without associ-
ated caries (cavities) or advanced gum disease.
Biting on the area of tooth fracture can cause
severe, sharp pains. Tooth fractures are usually
caused by chewing or biting hard objects, such as
hard candies, pencils, nuts, or ice. Treatment usu-
ally involves protecting the tooth with a crown.
However, if placing a crown does not relieve pain
symptoms, root canal surgery may be necessary.
cradle cap
A form of seborrheic dermatitis of the
scalp that is usually seen in infants but sometimes
found in older children. It is characterized by flak-
ing or scaling of the skin, which may also be red-
dened.
cramp, writer’s
A dystonia that affects the mus-
cles of the hand and sometimes the forearm and
that only occurs during handwriting. Similar focal
dystonias have been called typist’s cramp, pianist’s
cramp, musician’s cramp, and golfer’s cramp.
cranial
Toward (the opposite of caudad) or of
the head. See also Appendix B, “Anatomic
Orientation Terms.”
cranial arteritis
See 
arteritis, cranial.
cranial dystonia
See 
dystonia, cranial.
cranial nerves
The nerves of the brain, which
emerge from or enter the skull (the cranium), as
opposed to the spinal nerves, which emerge from
the vertebral column. There are 12 cranial nerves,
each of which is accorded a Roman numeral and a
name:
• Cranial nerve I: the olfactory nerve
• Cranial nerve II: the optic nerve
• Cranial nerve III: the oculomotor nerve
• Cranial nerve IV: the trochlear nerve
• Cranial nerve V: the trigeminal nerve
• Cranial nerve VI: the abducent nerve
• Cranial nerve VII: the facial nerve
• Cranial nerve VIII: the vestibulocochlear
nerve
• Cranial nerve IX: the glossopharyngeal
nerve
• Cranial nerve X: the vagus nerve
• Cranial nerve XI: the accessory nerve
• Cranial nerve XII: the hypoglossal nerve