dacrocystitis (dak-rē-ŏ-sis-TĪT-ĭs): Inflammation of the tear (lacrimal) sac.

dacryocystorhinostomy (dak-rē-ŏ-sis-tŏ-rī-NOS-tŏ-mē):

deamination (dē-am-ĭ-NĀ-shŏn): The removal of an amino group from a molecule.

debride, debridement (di-BRĒD, di-BRĒD-mĕnt): Remove damaged tissues and cell debris from a wound or burn to prevent infection and promote healing.

deep (DĒP): Describes a position farther from the surface of the body.

deep lymphatic vessels (dĕp lim-FAT-ik VES-ĕls): Lymphatic vessels of the organs.

defensins (dē-FĔN-sĭns): The lysozyme enzyme and proteins which have antibacterial properties.

dehydration (dē-hī-DRĀ-shŏn): Loss of fluids/water is greater than what is taken in.

dendrite (DEN-drīt): One of many branchlike processes that extends from the neuron cell body and functions as a contact for incoming signals (synapses) from other neurons or sensory cells.

dendritic cells (den-DRIT-ik): Pertaining to dendrites.

dermabrasion (DĔRM-ă-brā-zhŏn): Procedure to remove superficial scars using sandpaper or revolving wire brushes.

dermatitis (dĕr-mă-TĪT-ĭs): Inflammation of the skin.

dermatoautoplasty (dĕr-mă-tō-AW-tō-plăs-tē): Surgical repair using one’s own skin.

dermatoconiosis (dĕr-mă-tō-kō-nē-Ō-sĭs): Abnormal condition of the skin caused by dust.

dermatofibroma (dĕr-mă-tō-fī-BRŌ-mă): Fibrous tumor of the skin.

dermatoheteroplasty (dĕr-mă-tō-HĔT-ĕr-ō-plăs-tē): Surgical repair using skin from others.

dermatologic (dĕr-mă-TŎL-ō-jik): Pertaining to dermatology.

dermatologist (dĕr-mă-TŎL-ō-jĭst): Physician who specializes in treating diseases and disorders of the skin.

dermatology (dĕr-mă-TŎL-ō-jē): Study of the skin.

dermatome (DĔR-mă-tōm): Instrument used to cut skin.

dermatopathology (dĕr-măt-ō-pă-THOL-ō-jē): Study of diseases of the skin.

dermatoplasty (DĔR-măt-ō-plas-tē): Plastic surgery of the skin.

dermis (DĔR-mĭs): The layer of skin that is made of dense, irregular connective tissue that houses blood vessels, hair follicles, sweat glands, and other structures.

descending tract (dē-SEN-ding trakt): Central nervous system fibers carrying motor commands from the brain to the spinal cord or periphery.

detrusor (dē-TRŪ-zŏr): A muscle which forms a layer of the wall of the bladder.

diabetes mellitus (DM) (dī-ă-BĒT-ēz): An endocrine system disorder in which the pancreas does not produce insulin or the cells of the body do not respond to insulin. This results in high levels of glucose in the blood.

diapedesis (dī-ă-pĕ-DĒ-sĭs): The passage of blood cells through the intact walls of the capillaries, typically accompanying inflammation.

diaphoresis (dī-ă-fŏ-RĒ-sĭs): Profuse, excessive sweating.

diaphragm (dī-ă-FRAM): A flat, dome shaped muscle located at the base of the lungs and thoracic cavity.

diaphragmatic (dī-ă-frăg-MAT-ik): Pertaining to the diaphragm.

diaphragmatocele (dī-ă-frăg-MAT-ŏ-sēl): Hernia of the diaphragm.

diarthrosis (dī-ar-THRŌ-sĭs): Freely moveable joints.

diastole (dī-AS-tŏ-lē): Phase in the cardiac cycle where heart muscles relax allowing the chambers to fill with blood.

diastolic pressure (dī-AS-tŏ-lic): The diastolic pressure is the lower value (usually about 80 mm Hg) and represents the arterial pressure of blood during ventricular relaxation, or diastole.

diencephalon (dī-ĕn-SEF-ă-lŏn): Region of the adult brain that retains its name from embryonic development and includes the thalamus and hypothalamus.

dilation and curettage (D&C) (dī-LĀ-shŏn and kū-rĕ-TĂZH): A procedure where the cervix is dilated (widened) and a curette (a sharp instrument) is used to remove the lining of the uterus. This procedure is conducted when there is abnormal bleeding from the uterus and also to remove any products of conception, for example following an incomplete miscarriage or abortion.

diplopia (dip-LŌ-pē-ă): Double vision.

direct pathway: Connections within the basal nuclei from the striatum to the globus pallidus internal segment and substantia nigra pars reticulata that disinhibit the thalamus to increase cortical control of movement.

diskectomy (dis-KEK-tŏ-mē): Excision of the intervertebral disk.

diskitis (dis(k)-ĪT-ĭs): Inflammation of the intervertebral disk.

distal (DIS-tăl):  Describes a position in a limb that is farther from the point of attachment or the trunk of the body.

distended (dis-TEN-ded): Stretch out.

diuresis (dī-yŭ-RĒ-sĭs): Condition of urine passing through.

diverticulectomy (dī-vĕr-tĭk-ū-LĔK-tō-mē): Excision of the diverticula.

diverticulitis (dī-vĕr-tik-yŭ-LĪT-ĭs): Inflammation of the diverticulum.

diverticulosis (dī-vĕr-tik-yŭ-LŌ-sĭs): Abnormal condition of having diverticula.

dorsal (posterior) nerve root (DOR-săl (pŏs-TĒ-rē-or) nĕrv root): Axons entering the posterior horn of the spinal cord.

douching (doosh-ing): Washing the vagina with fluid.

ductus arteriosus (DŬK-tŭs ăr-tē-rē-Ō-sŭs): Connection between pulmonary trunk and aorta in the fetal heart.

ductus deferens (DŬK-tŭs DEF-ĕ-rĕnz): Duct that transports sperm from the epididymis through the spermatic cord and into the ejaculatory duct.

duodenal (doo-ŏ-DĒN-ăl): Pertaining to the duodenum.

dura mater (DOOR-ă MĀT-ĕr): Tough, fibrous, outer layer of the meninges that is attached to the inner surface of the cranium and vertebral column and surrounds the entire CNS.

duritis (dū-RĪ-tĭs): Inflammation of the dura mater.

dysentery (DIS-ĕn-ter-ē): Inflammation of the intestine presenting with abdominal pain and bloody diarrhea.

dyskinesia (dis-kĭ-NĒ-zh(ē-)ă): Condition of difficult movement.

dysmenorrhea (dis-men-ŏ-RĒ-ă): Painful periods.

dyspareunia (dis-pă-ROO-nē-ă): Painful intercourse.

dyspepsia (dis-PEP-shă, sē-ă): Difficult digestion.

dysphagia (dis-FĀ-j(ē-)ă): Difficulty swallowing.

dysphasia (dis-FĀ-zh(ē-)ă): Condition of difficulty speaking.

dysphonia (dis-FŌ-nē-ă): Condition of difficult speaking (voice).

dyspnea (dis(p)-NĒ-ă): Difficulty breathing.

dystocia (dis-TŌ-sh(ē-)ă): Labor that is difficult.

dystrophy (DIS-trŏ-fē): Abnormal development.

dysuria (dis-ŪR-ē-ă): Difficult or painful urine.