| Term | Definition | Pronunciation |
| /d | per day | |
| D&C | dilatation and curettage | |
| D&V | diarrhea & vomiting | |
| dacry/o | tears | |
| dacryoadenitis | Inflammation of the lacrimal glands (the eye’s tear-producing glands). | dak″re-o-ad″ĕ-ni´tis |
| dacryocystitis | Inflammation of the lacrimal sac. | |
| dactyl/o | fingers, toes | |
| dactylitis | Painful inflammation of the fingers or toes. | |
| dander | Fine, dry scales from the scalp. | |
| dandruff | Excessive shedding of dry scaly material from the scalp. | |
| dantrolene | Muscle relaxant drug. | |
| dark adaptation | Adjustment of the retina and pupil of the eyes under conditions of low light enabling increased sensitivity to light. | |
| DAW | dispense as written | |
| dB | decibel | |
| DBP | diastolic blood pressure | |
| dc | discontinue | |
| DDx | differential diagnosis | |
| de- | lack of, without, less, down | |
| DEA | Drug Enforcement Agency | |
| deafness | A general term for the complete loss of the ability to hear from both ears. | |
| death | Irreversible cessation of all bodily functions. | |
| debridement | A procedure used to remove dead tissue and contaminated substances from a wound, by soaking or excising. | da-brēd-maw´ |
| deca- | ten | |
| decapitation | Removal of the head. | |
| decay | The gradual decomposition of dead organisms after death. | |
| deceleration | A decrease in the rate of speed. | |
| deci- | one tenth | |
| decibel | A unit for comparing levels of power on a logarithmic scale. Commonly used for measuring sound. | |
| decidua | The membrane lining the wall of the uterus during pregnancy. | |
| decongestant | A substance that reduces nasal congestion. | |
| decubitus | The recumbent position. Lying on one's side. | |
| deep | Below the surface of the skin or within body cavity or limbs. | |
| deet | A common insect repellent. | |
| defamation | False written or spoken statements that are known to be false and that are damaging to the reputation of a person, group or organization. | |
| defibrillation | Use of an electronic device to give an electric shock to the heart to reestablish normal cardiac rhythm. | de-fib″rĭ-la´shun |
| degeneration | The gradual loss of function of a cell, tissue or organ. | |
| dehydration | The condition that results from excessive loss of water from a living organism. | |
| deja vu | A subjective feeling that a current experience is a repetition of a previous experience. | |
| delirium | A state of mental confusion that can occur due to illness, surgery or using certain medications. | dĕ-lēr´e-um |
| delirium tremens | The most severe form of alcohol withdrawal, causing confusion, irregular heart rate, and sweating. | dĕ-lēr´e-um trē′mənz |
| deltoid | Thick triangular muscle in the shoulder whose function is to abduct, flex, and extend the arm. | |
| delusion | A belief that is clearly false. | dĕ-lū'zhŭn |
| dem/o | people, population | |
| dementia | A group of symptoms caused by brain disorder. Not a specific disease. Causes are peripheral vascular disease, stroke, toxins, or Alzheimer's. | dĕ-men´shah |
| demi | half | |
| dendrite | Short branches of the nerve cell body that receive stimuli from other neurons. | |
| dengue | An acute febrile disease transmitted by the bite of infected Aedes mosquitoes. It occurs in tropical regions and is characterized by fever, severe pain, headache and rash. | |
| denial | Refusal to admit the truth or reality of a situation or experience. | |
| dent/i | teeth | |
| dentin | The main material of teeth. It is surrounded by pulp, covered by enamel on the crown and cementum on the root. | |
| deodorant | A substance that represses or masks odors. | |
| deoxyribonucleic acid | The primary carrier of genetic information. It consists of two chains of nucleotides that are twisted into a double helix and joined by hydrogen bonds between complementary bases. | |
| dependence | The state of reliance or subservience to another person or a substance. | |
| depersonalization | A feeling of unreality concerning the self or the environment. | |
| depreciation | Decline in value of capital assets over time. | |
| depression | 1) A sunken or hollow area. 2) Mental state of feeling sad, lonely, discouraged, hopeless or dejected. | |
| deprevation | The loss or lack of something that is needed. | |
| derailment | Mental disorder marked by speech consisting of a sequence of unrelated or remotely related ideas. | |
| derivative | Something produced as a modification of another object or thought. | |
| Derm | dermatology | |
| derm/o | skin | |
| derma- | skin | |
| dermat/o | skin | |
| dermatitis | Inflammation of the skin. May be caused by allergic reaction, drugs, infection or sun exposure. | der'mă-tī'tis |
| dermatology | A medical specialty concerned with the structure, functions, diseases and treatment of the skin. | |
| dermis | A layer of vascularized connective tissue underneath the epidermis. Embedded in or beneath it are glands, hair follicles, nerves and lymphatic vessels. | |
| desicc/o | drying | |
| desiccation | Removal of moisture from a substance. | |
| -desis | bind, fixation | |
| desm/o | ligament | |
| desmoid tumor | A dense, fibrous neoplasm. Occurs on the abdomen, upper arms, neck and head. | |
| desmosomes | An area of contact between adjacent cells, particularly epithelia. | |
| detergent | A cleaning agent. | |
| detoxification | The removal of poisons, alcohol or drugs and their effects from a patient. | |
| detrition | Wearing away by use or friction. | |
| deviant | Pertaining to an object or person that departs from normal. Abnormal. | |
| dew point | The temperature at which water vapor in the air condenses to liquid. | |
| dextr/o | right | |
| DI | diabetes insipidus | |
| di- | two, twice, double | |
| dia- | complete, through | |
| diabetes insipidus | A hormonal condition that causes the individual to have excessive and frequent urination. Inadequate ADH secretion. | insip′idəs |
| diabetes mellitus | A grouping of diseases that affect how the body uses glucose. Type I is lack of insulin, Type II is insulin resistance. | mel´ətəs |
| diabetic retinopathy | The most common diabetic eye disease. It occurs when blood vessels in the retina are damaged. Leading cause of blindness in working age adults. | ret″ĭ-nop´ah-the |
| diagnosis | The determination of the nature of a disease or condition, or the distinguishing of one disease or condition from another. | |
| diagnosis-related groups | A system for classifying patient care by relating common characteristics such as diagnosis, treatment, and age to an expected consumption of hospital resources and length of stay. | |
| dialysis | A therapeutic procedure used in patients with kidney failure for removal of harmful wastes and fluids from the blood. | di-al´ĭ-sis |
| diaper rash | Dermatitis of the buttocks and thighs due to contact with urine or feces. | |
| diaphoresis | Profuse sweating that is artificially induced. | dī′ə-fə-rē′sĭs |
| diaphragm | The muscle sheet that that separates the thoracic cavity from the abdomen. The diaphragm's contraction and relaxation changes the volume of the thoracic cavity, aiding breathing. | di´ah-fram |
| diarrhea | The onset of three or more loose or liquid bowel movements in a day. | di″ah-re´ah |
| diastole | Part of the heart rhythm when the ventricles passively relax and refill with blood. | di-as´to-le |
| diastolic blood pressure | Atrial blood pressure during diastole when the heart is resting. The second number in a blood pressure reading. | dī′əstol′ik |
| diathesis | Genetic predisposition to certain diseases or abnormalities. | |
| DIC | disseminated intravascular coagulation | |
| dicrotic | A heartbeat with two separate peaks. | |
| dielectric | Insulating material that can be polarized by an applied electric field. | |
| dietary fiber | Indigestible carbohydrate materials. Can be soluble or insoluble in water. | |
| dietetic | Pertaining to food and nutrition. | |
| dif- | separation, taking apart, reversal | |
| differential diagnosis | Distinguishing between two or more conditions having similar symptoms by systematic clinical comparison. | |
| differentiation | The acquisition of functions or forms different that the original. | |
| diffusion | The process of particles in gases and liquids to move from areas of high concentration to areas of lower concentration resulting in even distribution of such particles. | |
| dig | digitalis; digoxin | |
| digestion | The process of converting food into absorbable substances for metabolism and use by the body. | |
| digestive system | A group of structures, organs and glands stretching from the mouth to the anus, that breakdown food substances, absorb nutrients and remove waste. | |
| digit/o | finger, toe | |
| digitalis | Medicines that strengthen heart contraction and to slow heart rates, particularly for atrial fibrillation. | dij″ĭ-tal´is |
| digitization | The conversion of images, sounds or text into a digital form. | |
| dil | dilute; diluted | |
| dilat/o | enlarge, expand | |
| dilation | Causing the increase in the diameter of an organ, vessel or body opening. | |
| diopter | A unit of measurement of the refractive power of a lens. | |
| dioxin | Highly toxic, persistent environmental pollutant. A contaminant of a widely used herbicide. | |
| diphtheria | A bacterial infection of the upper respiratory tract that causes a thick web to form in the back of the throat. May be fatal. Preventable with immunization. Can also damage heart muscle and nerves. | dif-thēr´e-ah |
| dipl/o | double, two-sided | |
| diplegia | Paralysis involving both sides of the body. | |
| diplopia | Double vision. | dĭ-plo´pe-ah |
| dips- | thirst | |
| -dipsia | thirst | |
| dipsomania | Uncontrollable, recurring craving for alcohol. | |
| dis- | twice, apart, not | |
| disc | A rounded, flat plate. | |
| discharge | To release. The substance that is released. | |
| disclosure | The revealing of information. | |
| disease | A disorder of an organ or body function. Characterized by signs and symptoms. | |
| disinfectant | Substance that kills or inhibits harmful microorganisms. | |
| disinfection | Killing pathogens or rendering them harmless. | |
| dislocation | Displacement of a body part from its normal position. Commonly used to refer to a bone displaced from a joint. | |
| disorientation | A mentally confused state. Loss of one's bearings. | |
| dissection | The separation of tissues for surgical reasons or for analysis. | |
| dissociation | Separation of a particular of thoughts or emotions from normal consciousness. | |
| dissolve | To disperse a solid in a solution. | |
| dist/o | distant, far | |
| distal | farthest from the origin | dis´tal |
| distemper | Highly contagious and dangerous viral diseases of animals, particularly dogs. | |
| distillation | A process of separating the components of a liquid mixture by vaporization and condensation. | |
| distortion | A state of being twisted out of shape. A defense mechanism to disguise unacceptable thoughts. | |
| diuresis | Increased excretion of urine. | di″u-re´sis |
| diuretics | Medication that promote the excretion of urine, decreasing fluids in the blood vessels and reducing blood pressure. Also known as water pills. | |
| diurnal | Daily or relating to daylight hours. | |
| diverticulitis | An inflammation in the diverticula of the intestinal tract. | di″ver-tik″u-li´tis |
| diverticulosis | The presence of multiple pouches, usually in the colonic or gastric wall. | di″ver-tik″u-lo´sis |
| diverticulum | A pouch or sac developed from a tubular or saccular organ, such as the gastrointestinal tract. | |
| DJD | degenerative joint disease | |
| DKA | diabetic ketoacidosis | |
| dL | deciliter | |
| DM | diabetes mellitus | |
| DNA | deoxyribonucleic acid | |
| DNR | do not resuscitate | |
| DOA | dead on arrival | |
| DOB | date of birth | |
| DOE | dyspnea on exertion | |
| dolich/o | long | |
| dolor/o | pain | |
| dominant | Exhibiting a ruling influence. In genetics, capable of expression when carried by only one of a pair of homologous chromosomes. | |
| donor | A human, animal or other organism that provides tissue for another body. | |
| dopamine | A central nervous system neurotransmitter. | |
| doppler effect | Changes in the observed frequency of sound, light, or radio waves due to the relative motion of source and observer. | |
| dors/o | back of body | |
| dorsal | Pertaining to the back or posterior. | |
| dorsiflexion | The movement of the ankle joint that brings the dorsal (top region) of the foot towards the shin. | dor″sĭ-flek´shun |
| dorsum | top of the foot | dor´sum |
| down syndrome | A congenital disorder characterized by small size, hypotonia, protruding tongue, small ears, short, broad hands and cognitive impairment. | |
| DPL | diagnostic peritoneal lavage | |
| DPT | diphtheria, pertussis, tetanus (vaccine) | |
| dr | dram | |
| drainage | The removal of fluids or discharges from the body, such as from a wound, sore, or cavity. | |
| DRE | digital rectal examination | |
| DRG | diagnosis-related group | |
| drom/o | running | |
| -drome | running | |
| dry eye syndrome | Corneal and conjunctival dryness due to deficient tear production. | |
| dry socket | An inflammation of a tooth socket, that can occur after tooth extraction, caused by the disintegration of a blood clot. | |
| DSB | drug-seeking behavior | |
| DTR | deep tendon reflex | |
| DTs | delirium tremens | |
| DUB | dysfunctional uterine bleeding | |
| duct/o | to lead | |
| duoden/o | duodenum | |
| duodenitis | Inflammation of the duodenum section of the small intestine. | |
| duodenum | The proximal (first) portion of the small intestine, extending from the pylorus to the jejunum. | |
| dur/o | hard, dura mater | |
| dura mater | The dense, leathery membrane covering and protecting the brain and spinal cord. | du´rah ma´ter |
| DVT | deep vein thrombosis | |
| dwarfism | Abnormally short in stature. | |
| DWI | driving while intoxicated | |
| Dx | diagnosis | |
| dynam/o | power, strength | |
| -dynia | pain | |
| dys- | bad, painful, abnormal | |
| dysarthria | Difficulty in articulating words caused by impairment of the pharynx, larynx, tongue, or face muscles. | |
| dysentery | Acute inflammation of the intestine marked by frequent watery stools, often with blood and by pain, fever, and dehydration. | |
| dysgenesis | Defective development. | |
| dyskinesia | Involuntary muscle movements of the face, trunk, neck and extremities and difficulty with voluntary movements. Often associated with the use of certain medications. | dis-ki-ne´zhah |
| dyslexia | A common condition that affects the way the brain processes written and spoken language. | dis-lek´se-ah |
| dysmenorrhea | Painful cramps that can occur immediately before or during the menstrual period. | dis″men-ŏ-re´ah |
| dyspepsia | Impaired digestion, especially after eating. | dis-pep´se-ah |
| dysphagia | Difficulty in swallowing. | dis-fa´jah |
| dysphonia | Difficulty in speaking. | dis-fo´ne-ah |
| dysplasia | Abnormal development in tissues or organs. | |
| dysplastic nevi | Unusual, benign moles that may resemble melanoma. | dis-plastik nēvŭs |
| dyspnea | Difficult or labored breathing. Can indicate heart failure or a respiratory abnormality. | disp-ne´ah |
| dyssomnia | A disorder in which normal sleep patterns are disrupted. | |
| dystocia | Difficult childbirth. | |
| dystonia | A disorder characterized by involuntary muscle contractions that cause slow repetitive movements or abnormal postures. | dis-to´ne-ah |
| dystrophy | Any abnormal condition caused by defective nutrition | |
| dysuria | Painful or difficult urination. | |