Dictionary

coccyx The small tail-like bone at the bottom of the spine, very near the anus. It is the lowest part of the spinal column. Also known as tailbone.

coccygeal vertebrae The three to five (the average number is four) rudimentary vertebrae that make up the coccyx.

coccus A bacterial cell that has the shape of a sphere. Coccus is part of the name of a number of bacteria, such as enterococcus, meningococcus, pneumococcus, staphylococcus, and streptococcus.

cocci The plural of coccus.

cocaine A substance derived from the leaves of the coca plant that is a bitter, addictive substance formerly used as an anesthetic. Safer anesthetics than cocaine were developed in the 20th century, although it is still used as an injectable anesthetic by some dentists. Synthetic alternatives, such as procaine, are used far more widely. Tragically,…

coated stent A tiny cage to prop open an artery and prevent it from closing again, that is coated with a drug. The stent is inserted into a coronary artery, usually just after an angioplasty has been done, to keep open the vessel. The stent slowly releases the drug with which it is coated. Coated…

coarctation of the aorta Congenital constriction of the aorta that impedes the flow of blood below the level of the constriction and increases blood pressure above the constriction. Symptoms may not be evident at birth but may develop as soon as the first week after birth, with congestive heart failure or high blood pressure that…

coarctation A narrowing, stricture, or constriction of an artery. The sides of the vessel at the point of a coarctation appear to be pressed together.

coal miner’s pneumoconosis See black lung disease.

coagulation, blood See blood coagulation.

CNS prophylaxis Chemotherapy or radiation therapy to the central nervous system (CNS) as a preventive treatment. CNS prophylaxis is given to kill cancer cells that may be in the brain and spinal cord, even though no cancer has been detected there.

CNS Central nervous system.