Coronary (Lat. corona, a crown).  A term applied to vessels and nerves which encircle parts, as the coronary arteries of the heart.

Coronoid (Gr. koro#x3CE;ne, a crow).  Like a crow’s beak; thus the coronoid process of the ulna.

Cricoid (Gr. krikos, a ring, and eidos, form).  A cartilage of the larynx resembling a seal ring in shape.

Crystalline Lens (Lat. crystallum, a crystal).  One of the humors of the eye; a double-convex body situated in the front part of the eyeball.

Cumulative.  A term applied to the violent action from drugs which supervenes after the taking of several doses with little or no effect.

Cuticle (Lat. dim. of cutis, the skin).  Scarf skin; the epidermis.

Cutis (Gr. sky#1FE6;tos, a skin or hide).  The true skin, also called the dermis.

Decussation (Lat. decusso, decussatum, to cross).  The crossing or running of one portion athwart another.

Degeneration (Lat. degenerare, to grow worse, to deteriorate).  A change in the structure of any organ which makes it less fit to perform its duty.

Deglutition (Lat. deglutire, to swallow).  The process of swallowing.

Deltoid.  Having a triangular shape; resembling the Greek letter D (delta).

Dentine (Lat. dens, dentis, a tooth).  The hard substance which forms the greater part of a tooth; ivory.

Deodorizer.  An agent which corrects any foul or unwholesome odor.

Dextrin.  A soluble substance obtained from starch.

Diabetes Mellitus (Gr. dia, through, baino, to go, and me#x3AD;li, honey). 
Excessive flow of sugar-containing urine.

Diaphragm (Gr. diaphrasso, to divide by a partition).  A large, thin muscle which separates the cavity of the chest from the abdomen.

Diastole (Gr. diastello, to dilate).  The dilatation of the heart.

Dietetics.  That part of medicine which relates to diet, or food.

Diffusion of Gases.  The power of gases to become intimately mingled.

Diploee (Gr. diploo, to double, to fold).  The osseous tissue between the tables of the skull.

Dipsomania (Gr. dipsa, thirst, and mania, madness).  An insatiable desire for intoxicants.  Disinfectants.  Agents used to destroy the germs or particles of living matter that are believed to be the causes of infection.

Dislocation (Lat. dislocare, to put out of place).  An injury to a joint in which the bones are displaced or forced out of their sockets.

Dissection (Lat. dis, apart, and seco, to cut).  The cutting up of an animal in order to learn its structure.

Distal (Lat. dis, apart, and sto, to stand).  Away from the center.

Duct (Lat. duco, to lead).  A narrow tube.

Duodenum (Lat. duodeni, twelve).  The first division of the small intestines, about twelve fingers’ breadth long.