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Medical Dictionary: h

Word	Definition
H	hydrogen
H+	hydrogen ion
h/o	history of
habit	A recurrent, often unconscious pattern of behavior that is regularly manifested.
hair	A threadlike specialized epidermal structure developing from a papilla sunk in the dermis.
hair follicle	A tube-like invagination of the epidermis from which the hair shaft develops and into which the sebaceous glands open. The hair follicle is lined by a cellular inner and outer root sheath of epidermal origin and is invested with a fibrous sheath derived from the dermis.
halit/o	breath
halitosis	A foul breath odor resulting from poor oral hygiene, dental or oral infections, or the ingestion of certain foods.
hallucination	Sensing things while awake that appear to be real, but instead have been created by the mind, common in delirium.
hallux valgus	A bunion. A deformity of the joint connecting the big toe to the foot.
hand	The distal part of the arm beyond the wrist consisting of the carpus, metacarpus, and fingers.
hapl/o	simple, single
HAV	hepatitis A virus
HBP	high blood pressure
HBV	hepatitis B virus
HCG	human chorionic gonadotropin
HCP	health care professional
HCT,	hematocrit
HCV	hepatitis C virus
HD	hearing distance
HDL	high-density lipoprotein
HDV	hepatitis D
head	The upper part of the body containing the brain, mouth, and sense organs.
headache	Pain in the cranial region.
hearing	The ability to perceive sounds.
heart	The hollow, muscular organ that maintains the circulation of the blood.
heart arrest	Cessation of heart beat.
heart block	Impaired conduction of cardiac impulse that can occur anywhere along the conduction pathway, such as between the sinoatrial node and the right atrium (SA block) or between atria and ventricles (AV block).
heart failure	A heterogeneous condition in which the heart is unable to pump sufficient blood to meet the metabolic need of the body.
heart murmurs	Heart sounds caused by vibrations resulting from the flow of blood through the heart.
heart septum	This structure includes the thin muscular atrial septum between the two heart atria, and the thick muscular ventricular septum between the two heart ventricles.
heart sounds	The sounds heard over the cardiac region produced by the functioning of the heart.
heart valves	Flaps of tissue that prevent regurgitation of blood from the ventricles to the atria or from the pulmonary arteries or aorta to the ventricles.
heartburn	Substernal pain or burning sensation, usually associated with regurgitation of gastric juice into the esophagus.
heat exhaustion	A clinical syndrome caused by heat stress, such as over-exertion in a hot environment or excessive exposure to sun.
heat stroke	A condition caused by the failure of body to dissipate heat in an excessively hot environment or during physical exertion in a hot environment. The body temperature is dangerously high with red, hot skin accompanied by delusions; convulsions; or coma. It can be a life-threatening emergency and is most common in infants and the elderly. Also called sunstroke.
hect-	one hundred
hedon/o	pleasure
heel spur	A bony outgrowth on the lower surface of the heel bone.
helc/o	ulcer
heli/o	sun
hem/o	blood
hemangioma	A birthmark that commonly appears as a bright red nodule of blood vessels in the skin. Grows during the first year of life and then recedes over time. Also called a strawberry mark.
hemarthrosis	Bleeding into the joints.
hemat/o	blood
hematemesis	Vomiting blood.
hematocolpos	An accumulation of menstrual blood in the vagina.
hematocrit	The percentage by volume of red blood cells in a given sample.
hematology	The medical specialty focused on the diagnosis, treatment and prevention of blood diseases.
hematoma	An abnormal collection of blood outside of a blood vessel. A bruise.
hematometra	An accumulation of menstrual blood in the uterus.
hematospermia	Blood in the semen.
hematuria	Red blood cells in the urine.
hemi-	half
hemianopia	The loss of part of the field of view on the same side, in both eyes. A common side effect of stroke or brain injury.
hemiparesis	Weakness or paralysis of the entire left or right side of the body. Caused by congenital conditions, trauma, stroke or tumors.
hemiplegia	Paralysis of one side of the body.
hemobilia	Bleeding into the biliary passages.
hemochromatosis	A disorder of iron metabolism where the body absorbs too much iron. Treatment is required to avoid organ damage. A genetic disorder. 8% of population is a carrier.
hemodialysis	A therapeutic procedure used with kidney failure involving removal of harmful wastes and fluids from the blood.
hemodynamics	The forces involved in the movement of the blood through the cardiovascular system.
hemoglobins	The oxygen-carrying proteins of erythrocytes (red blood cells).
hemopneumothorax	Collection both blood and air in the pleural cavity.
hemoptysis	Coughing up blood or blood-stained mucus from the respiratory tract.
hemorrhage	Bleeding or escape of blood from a vessel. Bleeding can occur externally or internally to the body.
hemorrhagic stroke	A stroke that occurs when a weakened blood vessel ruptures. Also called an aneurysm.
hemorrhoids	Swollen veins in the lower part of the rectum or anus.
hemospermia	Blood in the semen, often due to inflammation of the prostate or the seminal vesicles.
hemostasis	The complex body process which spontaneously stops hemorrhages. This includes vessel contraction and blood adhesion, aggregation and coagulation.
hemothorax	Hemorrhage within the pleural cavity, often from chest trauma.
heparin	An endogenous, short-acting anticoagulant.
hepat/o	liver
hepatic	Pertaining to the liver.
hepatitis	Inflammation of the liver caused by viral agents.
hepatoblastoma	A malignant neoplasm occurring in young children, primarily in the liver,
hepatocytes	A parenchymal liver cell.
hepatoma	A malignant tumor of the liver
hepatomegaly	Having an enlarged liver.
hepta-	seven
herbicides	Pesticides used to destroy vegetation, particularly weeds and grasses.
heredity	The transmission of traits encoded in genes from parent to offspring.
heredo-	heir, heredity
hermaphroditic	A plant or animal with both male and female sex organs.
herni/o	hernia
hernia	Abnormal protrusion of tissue, structure, or part of an organ through the bone, muscular tissue, or the membrane by which it is normally contained.
herniorrhaphy	Surgical repair of a hernia
herpes	An infection caused by a herpes simplex virus. Can affect the genitals, buttocks or anal areas. Oral herpes causes cold sores on the face or mouth.
herpes labialis	Cold sores caused by herpes simplex I.
heter-	different, other
heterophoria	A tendency for deviation of the eyes from parallelism, prevented by binocular vision.
heterosexuality	The sexual attraction between members of the opposite sex.
heterosis	Greater vigor of the first generation hybrid than is shown by either parent.
heuristics	A set of rules or methods for solving problems other than by algorithm. The solution is not guaranteed to be optimal, but sufficient for a given set of goals.
HEV	hepatitis E
hex-	six
-hexia	condition
HF	heart failure
HFOV	high frequency oscillatory ventilation
Hg	mercury
hgb	hemoglobin
HGF	human growth factor
HGSIL	high-grade squamous intraepithelial lesion
hiat/o	gap, opening, pause
hiatus	An aperture, gap or opening.
hiccup	A spasm of the diaphragm that causes a sudden inhalation followed by rapid closure of the glottis which produces a sound. Also called singultus.
hidr/o	sweat
hidrocystoma	A cystic form of sweat gland adenoma, created by the cystic proliferation of apocrine secretory glands.
hidrosis	The production and excretion of sweat.
hidrotic	Relating to or causing sweating.
high density lipoprotein	Cholesterol known as HDL that removes harmful cholesterol, reducing risk of heart problems.
hip	The region of the body around the joint between the top of the femur and side of the pelvis.
HIPAA	Health Insurance Portability and Accountability Act
hippocampus	A curved elevation of gray matter extending the entire length of the floor of the temporal horn of the lateral ventricle (see also temporal lobe). It has a central role in memory processes.
hippus	Rhythmic pupillary dilation and constriction, independent of changes in illumination or convergence.
hirsutism	Excessive hairiness in women, usually caused by hormonal imbalance.
hist/o	tissue
histamine	An amine found in body tissues released in allergic inflammatory reactions. It is a vasodilator, stimulant of heart rate and gastric secretion, constrictor of bronchial smooth muscle and also a centrally acting neurotransmitter.
histiocytes	Macrophages found in the tissues, as opposed to those found in the blood or serous cavities.
histiocytoma	A neoplasm containing histiocytes.
histiocytosis	Abnormal appearance of histiocytes.
histogram	A bar chart.
histology	The study of the structure of tissues on a microscopic level.
hiv	Human immunodeficiency virus.
hoarseness	An unnaturally rough quality of voice.
hod-	pathway
Hodgkin's lymphoma	A type of lymphoma, a cancer of tissue in the lymph nodes, spleen, liver, and bone marrow. The first sign is often an enlargement of lymph node.
holo-	entire, complete
holography	The recording of three-dimensional images form using a laser beams.
holter monitor	A device that continuously records EKGs for hours or a few days, used to diagnose abnormal cardiac rhythms.
home/o	same, not changed
homeostasis	The process of maintaining physiological equilibrium.
homosexuality	The sexual attraction or relationship between members of the same sex.
hordeolum	Blockage of an eyelid gland causing a small inflamed cyst at the lid margin. Also called a stye.
horm-	impulse, urge
hormone	Substances having a specific regulatory effect on the activity of an organ or organs.
hospice	A facility providing palliative and supportive care to a patient with a terminal illness and to the patient's family.
hospice care	Care provided to a dying person. Care may be provided in the home, in the hospital or in specialized facilities.
hospitalists	Physicians who are employed to work exclusively in hospital settings, often for managed care organizations.
HPI	history of present illness
HR	heart rate
HRT	hormone replacement therapy
HSIL	high-grade squamous intraepithelial lesion
HSV	herpes simplex virus
HTN	hypertension
humerus	The bone of the upper arm. It extends from the shoulder joint to the elbow joint.
huntington disease	An inherited disorder characterized by the onset of progressive chorea (involuntary, rapid, irregular, jerky movements) and dementia in middle age.
hx	history
hyal/o	glass-like
hyalin	A translucent substance occurring in pathological degeneration of tissues.
hydr-	water
hydr/o	water, fluid
hydremia	An excess of water in the blood.
hydrocele	Buildup of the normal fluid around the testicle, common in infants, self-resolving.
hydrocephalus	The buildup of excessive cerebrospinal fluid in the brain.
hydronephrosis	Abnormal enlargement of a kidney, sometimes caused by blockage of the ureter.
hygiene	The science and practices that promote or preserve health
hygr/o	moisture
hymen	A thin fold of mucous membrane situated at the orifice of the vagina.
hymen/o	membrane
hyper-	excessive, above
hyperalgesia	An abnormal increased sensation of pain, caused by damage to soft tissue containing nociceptors or injury to a peripheral nerve.
hyperbaric	At a pressure higher than atmospheric pressure.
hypercalcemia	Too much calcium in the blood.
hypercalciuria	Excretion of abnormally high level of calcium in the urine.
hypercapnia	Abnormal increase in carbon dioxide in the blood.
hyperemesis gravidarum	Severe, intractable vomiting during early pregnancy. Often needs IV fluids and anti nausea agents.
hyperemia	The presence of an increased amount of blood in a body part due to increase of blood flow into the area or due to obstruction of outflow of blood from the area.
hyperesthesia	Hyperesthesia is a condition in which someone becomes highly sensitized to sensory stimuli.
hyperglycemia	High blood sugar. A serious problem for diabetics.
hyperhidrosis	Excessive sweating.
hyperinsulinism	Abnormally high levels of insulin in the blood.
hyperkalemia	Abnormally high potassium concentration in the blood, usually due to acute renal failure.
hyperkinesia	Spontaneous involuntary movements.
hyperkinesis	Excessive movement of muscles of the body.
hyperlipidemia	Conditions with excess lipids (fats) in the blood.
hypernatremia	An excess of sodium in the blood.
hyperopia	Farsightedness. Distant objects can be seen clearly, but close ones do not come into proper focus.
hyperostosis	Abnormal thickening or growth of bone.
hyperoxaluria	Abnormally high amounts of oxalates in the urine.
hyperoxia	An excess of oxygen in tissues and organs.
hyperphagia	Overeating.
hyperphosphatemia	Abnormally high level of phosphates in the blood.
hyperpigmentation	Excessive pigmentation of the skin, usually as a result of increased epidermal or dermal melanin pigmentation, hypermelanosis. The condition may arise from exposure to the sun.
hyperpituitarism	Excessive hormone production by the pituitary gland.
hyperplasia	An abnormal increase in the number of cells in a tissue or organ without tumor formation.
hyperpnea	Deep breathing. Can be normal during exercise or abnormal due to anemia or sepsis.
hypersensitivity	Abnormally high response to an antigen.
hypersomnia	Excessive sleeping
hypersthenia	Excessive strength or tension.
hypertension	Persistently high systemic arterial blood pressure.
hyperthyroidism	Excessive hormone production by the thyroid.
hyperthyroxinemia	Abnormally elevated thyroxine level in the blood.
hypertonic	Having increased tone or tension.
hypertrichosis	Excessive hair growth at inappropriate locations.
hypertriglyceridemia	A condition of elevated levels of triglycerides in the blood.
hypertrophy	General increase in volume of a tissue or organ produced entirely by enlargement of existing cells.
hyperuricemia	An abnormally high concentration of uric acid in the blood. It is associated with gout and also hypertension.
hyperventilation	Breathing faster or deeper than is metabolically necessary causing an excessive intake of oxygen and a reduction carbon dioxide level in arterial blood.
hypesthesia	Absent or reduced sensitivity to cutaneous stimulation.
hyphema	Bleeding in the anterior chamber of the eye.
hypn/o	sleep
hypnosis	A state of increased receptivity to suggestion and direction, initially induced by the influence of another person.
hypo-	deficient, under
hypocalcemia	Abnormally low levels of calcium in the blood.
hypocapnia	Deficiency of carbon dioxide in arterial blood.
hypochondria	Anxiety about one's own health and belief that one is likely to become ill even though there is no medical evidence of illness.
hypochondriasis	An overwhelming fear of having a serious disease.
hypodermic	Beneath the skin.
hypogeusia	Diminished sense of taste.
hypoglycemia	Abnormally low blood glucose (blood sugar) levels, usually less than 70 mg/dl.
hypogonadism	Abnormally low functional activity of the gonads, with diminished growth and sexual development
hypohidrosis	Abnormally low or absent perspiration.
hypokalemia	Abnormally low potassium concentration in the blood.
hypokinesia	Abnormally diminished movement of body musculature.
hypomenorrhea	Extremely light menstrual blood flow.
hyponatremia	Insufficient sodium levels in the blood. Can be caused by loss of sodium or by increased and excessive body fluids.
hypoperfusion	Abnormally low blood flow through an organ.
hypoplasia	Underdevelopment of a tissue or organ.
hypopnea	Shallow or abnormally slow breathing.
hypospadias	A birth defect due to malformation of the urethra in which the urethral opening is below its normal location.
hypotension	Abnormally low blood pressure that can result in inadequate blood flow to the brain and other organs.
hypothermia	Lower than normal body temperature.
hypotonia	Poor muscle tone usually detected at birth or during infancy. It is reflected in the APGAR score.
hypotonic	Denoting decreased tone or tension.
hypotrichosis	Less than the normal amount of hair.
hypoventilation	Deficient ventilation of the lungs resulting is low oxygen levels and high carbon dioxide levels in the blood.
hypovolemia	An abnormally low volume of circulating blood.
hypoxemia	Oxygen deficiency in arterial blood.
hypoxia	Insufficient oxygen levels in body organs and tissues.
hypsi-	high
hyster/o	uterus
hysterectomy	Surgical removal of the uterus.
hysteria	Excessive or uncontrollable emotion, such as fear or panic.
hysterosalpingography	Fluoroscopic examination of the uterus and fallopian tubes.
hysteroscopy	Examination of the uterine cavity using an endoscope.
hysterotomy	An incision in the uterus, performed through either the abdomen or the vagina.
Hz	hertz (cycles per second)