Medical Glossary Index:

D

D and C- see Dilatation and Curettage

Debridement- surgical removal of dead, damaged, or infected tissue, or some foreign material from a wound or burn

Decompression sickness- the formation of gas bubbles in the body’s tissues as
a result of a scuba diver ascending too quickly from depth; commonly called the bends

Deep-vein thrombosis- the formation of a blood clot inside of a deep-lying vein, usually in the legs

Defecation- the passing of feces out of the body through the anus; a bowel movement

Defibrillation- a short electric shock to the chest to normalize an irregular heartbeat

Degenerative arthritis- the breakdown of the cartilage lining the bones in joints, usually weight-bearing joints (such as the knee); causes stiffness and pain (also called osteoarthritis)

Dehydration- excessive, dangerous loss of water from the body

Dementia- a gradual decline in mental ability usually caused by a brain disease, such as Alzheimer disease

Depilatory- a chemical hair remover

Depot injection- injection of a drug into a muscle; the drug is designed to absorb slowly into the body

Depression- feelings of hopelessness, sadness, and a general disinterest in life, which for the most part have no cause and may be the result of a psychiatric illness

Dermabrasion- removal of the surface layer of skin with a sanding wheel to treat scarring or to remove tattoos

Dermatitis- inflammation of the skin

Dermis- the inner skin layer

Desensitization- the process of making a person less allergic to a substance by injecting gradually increasing amounts of the substance; sometimes done to prevent anaphylactic shock

Detoxification- treatment given either to fight a person's dependence on alcohol or other drugs or to rid the body of a poisonous substance and its effects

Dextrocardia- a rare genetic condition in which the heart is located on the right side of the body, instead of the left

Dextrose- another name for the sugar glucose

Diabetes insipidus- a rare condition characterized by increased urine production

Diabetes mellitus- a common form of diabetes in which the body cannot properly store or use glucose (sugar), the body's main source of energy

Dialysis- a procedure to treat kidney failure in which artificial means are used to filter waste, maintain acid-base balance, and remove excess fluid from the body

Diaper rash- a common condition in babies in which the skin in the diaper area becomes irritated and red, usually because of exposure to urine, feces, or heat

Diaphragm- the large, dome-shaped muscle separating the abdomen and chest that contracts and relaxes to make breathing possible; also, a thin, rubber dome that
is used as a method of female contraception

Diastolic pressure- the blood pressure measured when the heart is at rest between beats

Diathermy- the use of high-frequency currents, microwaves, or ultrasound to produce heat in the body to increase blood flow, relieve pain, or destroy diseased tissue

Dilatation and Curettage- a procedure in which the vagina and cervix are widened and the lining of the uterus is scraped away to diagnose and treat disorders of the uterus

Diphtheria- a bacterial infection that causes a fever, headache, sore throat, and possibly death; diphtheria is rare in developed countries

Disk prolapse- a disorder in which one of the disks located between the vertebrae in the spine breaks down and the pulpy interior squeezes out, causing pressure on a nerve; commonly called a "slipped" or "ruptured" disk

Dislocation- displacement of the two bones in a joint

Distention- swelling, enlargement, or stretching

Diuretic- a drug that increases the amount of water in the urine, removing excess water from the body; used in treating high blood pressure and fluid retention

Diverticulitis- inflammation of diverticula (small sacs in the intestine's inner lining); can cause fever, pain, and tenderness

DNA- deoxyribonucleic acid; responsible for passing genetic information in nearly all organisms

Dominant gene- a gene that always produces its effect when it is present

Dopamine- a chemical that transmits messages in the brain and plays a role in movement

Down syndrome- a genetic disorder in which a person’s cells have 1 too many chromosomes, causing moderate to severe mental handicap and a characteristic appearance

Duchenne muscular dystrophy- a genetic condition in boys in which nerves degenerate and muscles get progressively weaker

Duodenal ulcer- an erosion in the inner lining of the wall of the first part of the small intestine (called the duodenum)

Duodenum- the first part of the small intestine, immediately following the stomach

Dysentery- a severe intestinal infection, causing abdominal pain and diarrhea with blood or mucus

Dyspnea- difficulty breathing

Dystrophy- any disorder in which cells become damaged or do not develop properly because they do not receive adequate nutrition