Dictionary of Medical Terms 4th Ed

breastbone of a patient clasped from behind forces the blockage out of the windpipe helco- /helkəυ/ prefix relating to an ulcer helcoplasty / helkəυpl sti/ noun a skin graft to cover an ulcer to aid healing

Helicobacter pylori / hel kəυb ktə pa lɔ ri / noun a bacterium found in gastric secretions, strongly associated with duodenal ulcers and gastric carcinoma

helicopter-based emergency medical services / hel kɒptə be st m! d ənsi med k(ə)l s! v s z/ plural noun full form of

HEMS

helio- /hi liəυ/ prefix relating to the sun heliotherapy / hi liəυ θerəpi/ noun treatment by sunlight or sunbathing

helium / hi liəm/ noun a very light gas used in combination with oxygen, especially to relieve asthma or sickness caused by decompression (NOTE: The chemical symbol is He.)

helix / hi l ks/ noun the curved outer edge of the ear

Heller’s operation / heləz ɒpə re ʃ(ə)n/ noun same as cardiomyotomy [After E. Heller

(1877–1964), German surgeon.]

Heller’s test / heləz test/ noun a test for protein in the urine [After Johann Florenz Heller (1813–71), Austrian physician]

Hellin’s law / hel nz lɔ / noun a finding which states that twins should occur naturally once in 90 live births, triplets once in 8,100 live births, quadruplets once in 729, 000 live births, and quintuplets once in 65, 610, 000 live births (NOTE: Since the 1960s the numbers have changed due to fertility treatment. For ex-

ample, twins now occur once in only 38 births.)

HELLP syndrome / help s ndrəυm/ noun a serious pre-eclamptic disorder which makes it necessary to terminate a pregnancy. Full form haemolysis-elevated liver enzymes–low platelet count syndrome

helminth / helm nθ/ noun a parasitic worm, e.g. a tapeworm or fluke

helminthiasis / helm n θa əs s/ noun infestation with parasitic worms

heloma /h ləυmə/ noun same as corn helper / helpə/ noun a person who helps someone to do something, especially without payment

helper T-cell / helpə ti sel/ noun a type of white blood cell that stimulates the production of cells that destroy antigens

hemeralopia / hemərə ləυpiə/ noun a usually congenital condition in which someone is able to see better in bad light than in ordinary daylight. Also called day blindness

hemi- /hemi/ prefix half

hemianopia / hemiə nəυpiə/ noun a state of partial blindness in which someone has only half the usual field of vision in each eye

hemiarthroplasty / hemi ɑ θrəυpl sti/ noun an operation to repair a joint which replaces one of its surfaces with an artificial substance, often metal

hemiatrophy / hemi trəf / noun a condition in which half of the body or half of an or-

gan or part is atrophied

hemiballismus / hemibə l zməs/ noun a sudden movement of the limbs on one side of the body, caused by a disease of the basal gan-

glia

hemicolectomy / hemikə lektəmi/ noun the surgical removal of part of the colon hemicrania / hemi kre niə/ noun a headache in one side of the head, as in migraine hemimelia / hemi mi liə/ noun a congenital condition in which someone has absent or ex-

tremely short arms or legs

hemiparesis / hemipə ri s s/ noun slight paralysis of the muscles of one side of the body

hemiplegia / hemi pli d ə/ noun severe paralysis affecting one side of the body due to damage of the central nervous system. Compare diplegia

hemiplegic / hemi pli d k/ adjective referring to paralysis of one side of the body hemisphere / hem sf ə/ noun half of a sphere

hemo- /hi məυ/ prefix US spelling of haemo- HEMS /hemz/ plural noun a system of delivering a paramedic crew to the scene of an accident or medical emergency by helicopter and then transporting patients to the nearest major hospital or specialist unit. Full form helicop- ter-based emergency medical services

mɒd(ə)l/ noun a model of nurse–patient relationships based on 14 basic principles of nursing. The main idea is that ‘the nurse does for others what they would do for themselves if they had the strength, the will, and the knowledge…but that the nurse makes the patient in-

dependent of him or her as soon as possible’.

Henle’s loop / henli z lu p/ noun same as loop of Henle [Described 1862. After Friedrich Gustav Jakob Henle (1809–85), Professor of Anatomy at Göttingen, Germany.]

Henoch-Schönlein purpura / henəkʃ! nla n p! pjυrə/, Henoch’s purpura /

henəks p! pjυrə/ noun a condition in which blood vessels become inflamed and bleed into the skin, causing a rash called purpura and also pain in the stomach and the joints, vomiting and diarrhoea. It often occurs after an upper respiratory infection, mostly in children aged two to 11. [Described 1832 by Schönlein and 1865 by Henoch. Eduard Heinrich Henoch (1820–1910), Professor of Paedriatrics at Berlin, Germany; Johannes Lukas Schönlein (1793– 1864), physician and pathologist at Würzburg, Zürich and Berlin.]

hep /hep/ noun same as hepatitis (informal) heparin / hepər n/ noun an anticoagulant substance found in the liver and lungs, and also produced artificially for use in the treatment of thrombosis

hepat- /h p t/ prefix same as hepato- (used

before vowels)

hepatalgia / hepə t ld ə/ noun pain in the

liver

hepatectomy / hepə tektəmi/ noun the surgical removal of part of the liver

hepatic /h p t k/ adjective referring to the

liver

hepatic artery /h p t k ɑ təri/ noun an artery which takes the blood to the liver hepatic cell /h p t k sel/ noun an epitheli-

al cell of the liver acini

hepatic duct /h p t k d"kt/ noun a duct which links the liver to the bile duct leading to

the duodenum

hepatic flexure /h p t k flekʃə/ noun a bend in the colon, where the ascending and

transverse colons join

hepaticostomy /h p t kɒstəmi/ noun a surgical operation to make an opening in the

hepatic duct taking bile from the liver hepatic portal system /h p t k pɔ t(ə)l

s stəm/ noun a group of veins linking to form the portal vein, which brings blood from the pancreas, spleen, gall bladder and the abdomi-

nal part of the alimentary canal to the liver hepatic vein /h p t k ve n/ noun a vein

which takes blood from the liver to the inferior vena cava

hepatis / hepət s/ porta hepatis hepatitis / hepə ta t s/ noun inflammation of the liver through disease or drugs

COMMENT: Infectious hepatitis and serum hepatitis are caused by different viruses called A and B, and having had one does not give immunity against an attack of the other. Hepatitis A is less serious than the B form, which can cause severe liver failure and death. Other hepatitis viruses have also been identified.

hepatitis A / hepəta t s e / noun a relatively mild form of viral hepatitis that is transmit-

ted through contaminated food and water hepatitis A virus / hepəta t s e va rəs/

noun a virus which causes hepatitis A. Abbr

HAV

hepatitis B / hepəta t s bi / noun a severe form of viral hepatitis that is transmitted by contact with infected blood or other body flu-

ids

hepatitis B virus / hepəta t s bi va rəs/ noun a virus which causes hepatitis B. Abbr

HBV

hepatitis C noun a form of viral hepatitis that is transmitted by contact with infected blood or other body fluids but is often without symptoms (NOTE: It was formerly called non-A, non-B hepatitis.)

hepatitis C virus noun a virus which causes

hepatitis C. Abbr HCV

hepatitis delta / hepə ta t s deltə/ noun

same as delta hepatitis

hepato- /hepətəυ/ prefix referring to the liver hepatoblastoma / hepətəυbl stəυmə/

noun a malignant tumour in the liver, made up of epithelial-type cells often with areas of im-

mature cartilage and embryonic bone hepatocele / hepətəυsi l/ noun a hernia of

the liver through the diaphragm or the abdominal wall

hepatocellular / hepətəυ seljυlə/ adjective referring to liver cells

hepatocellular jaundice / hepətəυseljυlə d ɔ nd s/ noun jaundice caused by

injury to or disease of the liver cells hepatocirrhosis / hepətəυs rəυs s/ noun

same as cirrhosis

hepatocolic ligament / hepətəυkɒl k l &əmənt/ noun a ligament which links the

gall bladder and the right bend of the colon hepatocyte / hepətəυsa t, h p təsa t/

noun a liver cell which synthesises and stores substances, and produces bile hepatogenous / hepə tɒd ənəs/ noun referring to or originating in the liver hepatogenous jaundice

hepatolenticular degeneration / hepətəυ len t kjυlə d d enə re ʃ(ə)n/ noun same as

Wilson’s disease

hepatoma / hepə təυmə/ noun a malignant tumour of the liver formed of mature cells, es-

pecially found in people with cirrhosis hepatomegaly / hepətəυ me&əli/ noun a

condition in which the liver becomes very

large

hepatosplenomegaly / hepətəυ spli nəυ me&əli/ noun enlargement of both the liver

and the spleen, as occurs in leukaemia or lym-

phoma

hepatotoxic / hepətəυ tɒks k/ adjective de-

stroying the liver cells

herald patch / herəld p tʃ/ noun a small spot of a rash such as pityriasis rosea which appears some time before the main rash herb /h! b/ noun a plant which can be used in preparing medicines

herbal / h! b(ə)l/ adjective referring to plants which are used as medicines

herbalism / h! bəl z(ə)m/ noun herbal medicine

herbalist / h! bəl st/ noun a person who treats illnesses or disorders with substances

extracted from plants

herbal medicine / h! b(ə)l med(ə)s n/ noun a system of medical treatment involving

the use of substances extracted from plants herbal remedy / h! b(ə)l remədi/ noun a

medicine made from plants, e.g. an infusion made from dried leaves or flowers in hot water

herd immunity / h! d mju n ti/ noun the fact of a group of people being resistant to a specific disease, because many individuals in the group are immune to or immunised against the microorganism which causes it hereditary /hə red t(ə)ri/ adjective passed as from parents to children through the genes

hereditary spherocytosis /hə red t(ə)risf ərəυsa təυs s/ noun same as acholuric

jaundice

heredity /hə red ti/ noun the process by which genetically controlled characteristics

pass from parents to children

Hering-Breuer reflexes / her ŋ brɔ ə

ri fleks z/ plural noun the reflexes which maintain the usual rhythmic inflation and de-

flation of the lungs

hermaphrodite /h! m frəda t/ noun a person with both male and female characteris-

tics

hermaphroditism /h! m frəda t z(ə)m/ noun a condition in which a person has both male and female characteristics

hernia / h! niə/ noun a condition in which an organ bulges through a hole or weakness in the wall which surrounds it. Also called rupture reduction of a hernia putting a hernia back

into the correct position

hernial / h! niəl/ adjective referring to a her-

nia

hernial sac / h! niəl s k/ noun a sac formed where a membrane has pushed through

a cavity in the body

herniated / h! nie t d/ adjective referring to

an organ which has developed a hernia herniated disc / h! nie t d d sk/ noun

displaced intervertebral disc

herniation / h! ni e ʃ(ə)n/ noun the development of a hernia

hernio- /h! niəυ/ prefix relating to a hernia hernioplasty / h! niəυ pl sti/ noun a surgical operation to reduce a hernia herniorrhaphy / h! ni ɔ rəfi/ noun a surgical operation to remove a hernia and repair the

organ through which it protruded herniotomy / h! ni ɒtəmi/ noun a surgical

operation to remove a hernial sac

heroin / herəυ n/ noun a narcotic drug in the form of a white powder derived from morphine

herpangina / h! p n d a nə/ noun an infectious disease of children, where the tonsils and back of the throat become inflamed and ulcerated, caused by a Coxsackie virus herpes / h! pi z/ noun inflammation of the skin or mucous membrane, caused by a virus,

where small blisters are formed

herpes simplex / h! pi z s mpleks/ noun

1. (Type I) a virus that produces a painful blister, called a cold sore, usually on the lips 2. (Type II) a sexually transmitted disease which

forms blisters in the genital region. Also called genital herpes

herpesvirus / h! pi z va rəs/ noun one of a group of viruses which cause herpes and chickenpox (herpesvirus Type I), and genital herpes (herpesvirus Type II)

COMMENT: Because the same virus causes herpes and chickenpox, anyone who has had chickenpox as a child carries the dormant herpesvirus in his or her bloodstream and can develop shingles in later life. It is not known what triggers the development of shingles, though it is known that an adult suffering from shingles can infect a child with chickenpox.

herpes zoster / h! pi z zɒstə/ noun inflammation of a sensory nerve, characterised by pain along the nerve and causing a line of blisters to form on the skin, usually found mainly on the abdomen or back, or on the face. Also called shingles, zona

herpetic /h! pet k/ adjective referring to herpes

herpetiformis /h! pet fɔ m s/ dermati-

tis herpetiformis

hetero- /hetərəυ/ prefix different heterochromia / hetərəυ krəυmiə/ noun a condition in which the irises of the eyes are

different colours

heterogametic / hetərəυ&ə met k/ adjective producing gametes with different sex chromosomes, as in the human male heterogeneous / hetərəυ d i niəs/ adjective having different characteristics or qualities

(NOTE: Do not confuse with heterogenous.) heterogenous / hetə rɒd nəs/ adjective

coming from a different source (NOTE: Do not

confuse with heterogeneous.)

heterograft / hetərəυ&rɑ ft/ noun tissue taken from one species and grafted onto an individual of another species. Compare hom-

ograft

heterologous /hetə rɒlə&"s/ adjective of a different type

heterophoria / hetərəυ fɔ riə/ noun a condition in which if an eye is covered it tends to squint

heteroplasty / hetərəυpl sti/ noun same as

heterograft

heteropsia / hetə rɒpsiə/ noun a condition

in which the two eyes see differently heterosexual / hetərəυ sekʃuəl/ adjective attracted to people of the opposite sex or relating to relations between males and females noun a person who is sexually attracted to people of the opposite sex. Compare bisexual, ho-

noun sexual attraction towards persons of the opposite sex

heterotopia / hetərəυ təυpiə/ noun 1. a state where an organ is placed in a different position from usual or is malformed or deformed

2. the development of tissue which is not natu-

ral to the part in which it is produced heterotropia /hetərəυ trəυpiə/ noun same

as strabismus

heterozygous / hetərəυ za &əs/ adjective having two or more different versions of a specific gene. Compare homozygous

hex- /heks/ prefix same as hexa- (NOTE: used

before vowels)

hexa- /heksə/ prefix six

HFEA abbr Human Fertilization and Embryology Authority

hGH abbr human growth hormone

HGPRT abbr hypoxanthine guanine phosphoribosyl transferase. HPRT

HI abbr hearing-impaired

hiatus /ha e təs/ noun an opening or space

hiatus hernia /ha e təs h! niə/, hiatal hernia /ha e t(ə)l h! niə/ noun a hernia where

the stomach bulges through the opening in the diaphragm muscle through which the oesophagus passes

Hib /h b/ abbr Haemophilus influenzae type B

Hib vaccine / h b v ksi n/ noun a vaccine used to inoculate against the bacterium Haemophilius influenzae that causes meningitis hiccup / h k"p/, hiccough noun a spasm in the diaphragm which causes a sudden inhalation of breath followed by sudden closure of the glottis which makes a characteristic sound

She had an attack of hiccups or had a hiccupping attack or got the hiccups. Also called singultus verb to make a hiccup

COMMENT: Many cures have been suggested for hiccups, but the main treatment is to try to get the patient to think about something else. A drink of water, holding the breath and counting, breathing into a paper bag, are all recommended.

Hickman catheter / h kmən k θitə/, Hickman line / h kmən la n/ noun a plastic tube which is put into the large vein above the heart so that drugs can be given and blood samples can be taken easily

hidr- /ha dr/ prefix referring to sweat hidradenitis / ha drədə na t s/ noun inflammation of the sweat glands

hidrosis /ha drəυs s/ noun sweating, especially when it is excessive

hidrotic /ha drɒt k/ adjective referring to sweating noun a substance which makes someone sweat

Higginson’s syringe / hi& nsənz s r n / noun a syringe with a rubber bulb in the centre that allows flow in one direction only, used mainly to give enemas [After Alfred Higginson (1808–84), British surgeon]

high-altitude sickness /ha lt tju d

s knəs/ noun same as altitude sickness high blood pressure / ha bl"d preʃə/

noun same as hypertension

high-calorie diet /ha k ləri da ət/ noun a diet containing over 4000 calories per day

high-density lipoprotein /ha dens ti l pəυ prəυtin/ noun a lipoprotein with a low

percentage of cholesterol. Abbr HDL high-energy food / ha enəd i fu d/ noun food such as fats or carbohydrates which contain a large number of calories and give a lot of energy when they are broken down in the body high-fibre diet /ha fa bə da ət/ noun a diet which contains a high percentage of cereals, nuts, fruit and vegetables

high-protein diet /ha prəυti n da ət/ noun a diet containing mostly foods high in protein and low in carbohydrates and saturated fat, adopted by people who are trying to lose weight

high-risk / ha r sk/ adjective referring to someone who is very likely to catch or develop a disease, develop a cancer or have an accident high-risk patient / ha r sk pe ʃ(ə)nt/ noun a patient who has a high risk of catching an infection or developing a disease

hilar / ha lə/ adjective referring to a hilum hilum / ha ləm/ noun a hollow where blood vessels or nerve fibres enter an organ such as a kidney or lung (NOTE: The plural is hila.) hindbrain / ha ndbre n/ noun the part of brain of an embryo from which the medulla oblongata, the pons and the cerebellum eventually develop

hindgut / ha nd&"t/ noun part of an embryo which develops into the colon and rectum hinge joint / h nd d ɔ nt/ noun same as ginglymus

hip /h p/ noun a ball and socket joint where the thigh bone or femur joins the acetabulum of the hip bone

hip bone / h p bəυn/ noun a bone made of the ilium, the ischium and the pubis which are fused together, forming part of the pelvic girdle. Also called innominate bone

hip fracture / h p fr ktʃə/ noun a fracture of the ball at the top of the femur

hip girdle / h p &! d(ə)l/ noun same as pelvic girdle

hip joint / h p d ɔ nt/ noun the place where the hip is joined to the upper leg. See illustration at PELVIS in Supplement

Hippel-Lindau / h pəl l ndaυ/ von Hip-

pel-Lindau syndrome

hippocampal formation / h pək mp(ə)l fɔ me ʃ(ə)n/ noun curved pieces of cortex inside each part of the cerebrum

hippocampus / h pəυ k mpəs/ noun a long rounded elevation projecting into the lateral ventricle in the brain

Hippocratic oath / h pəkr t k əυθ/ noun an ethical code observed by doctors, by which they will treat patients equally, put patients’

welfare first and not discuss openly the details of a patient’s case

hippus / h pəs/ noun alternating rapid contraction and dilatation of the pupil of the eye hip replacement / h p r ple smənt/ noun a surgical operation to replace the whole ball and socket joint at the hip with an artificial one

Hirschsprung’s disease / h əʃspr"ŋz dzi z/ noun a congenital condition where parts of the lower colon lack nerve cells, making peristalsis impossible, so that food accumulates in the upper colon which becomes swollen [Described 1888. After Harald Hirschsprung (1830–1916), Professor of Paediatrics in Copenhagen, Denmark.]

hirsute / h! sju t/ adjective with a lot of hair hirsutism / h! sju t z(ə)m/ noun the condition of having excessive hair, especially a condition in which a woman grows hair on the body in the same way as a man

hirudin /h ru d n/ noun an anticoagulant substance produced by leeches, which is injected into the bloodstream while the leech is feeding on a body

HIS abbr Health Information Service

hist- /h st/ same as histo- (NOTE: used before vowels)

histamine / h stəmi n/ noun a substance released in response to allergens from mast cells throughout the body. Histamines dilate blood vessels, constrict the cells of smooth muscles and cause an increase in acid secretions in the stomach.

histamine headache / h stəmi n hede k/

noun Horton’s syndrome

histamine receptor / h stəmi n r septə/ noun a cell which is stimulated by histamine. H1 receptors in blood vessels are involved in allergic reactions, H2 receptors in the stomach are involved in gastric acid secretion. histamine test / h stəmi n test/ noun a test to determine the acidity of gastric juice

histaminic / h stə m n k/ adjective referring to histamines

histaminic headache / h stəm n k he*

de k/ noun Horton’s syndrome

histidine / h stədi n/ noun an amino acid from which histamine is derived

histiocyte / h stiəυsa t/ noun a macrophage of the connective tissue, involved in tissue defence

histiocytoma / h stiəυsa təυmə/ noun a tumour containing histiocytes histiocytosis /h stiəυsa təυs s/ noun a condition in which histiocytes are present in the blood

histiocytosis X / h stiəυsa təυs s eks/ noun any form of histiocytosis where the cause is not known, e.g. Hand-Schüller-Christian disease

histo- /h stəυ/ prefix relating to the body’s tissue histology

histochemistry / h stəυ kem stri/ noun the study of the chemical constituents of cells and tissues and also their function and distribution, using a light or electron microscope to evaluate the stains

histocompatibility / h stəυkəmp tə b l * ti/ noun compatibility between the antigens of tissues from two individuals, important in transplants

histocompatible / h stəυkəm p t b(ə)l/ adjective referring to tissues from two individuals which have compatible antigens histogenesis / h stəυ d enəs s/ noun the formation and development of tissue from the

embryological germ layer

histogram / h stə&r m/ noun a way of displaying frequency values as columns whose height is proportional to the corresponding frequency a histogram showing numbers of pa-

tients with the condition in each age group histoid / h stɔ d/ adjective 1. made of or developed from a particular tissue 2. like standard tissue

histological / h stə lɒd k(ə)l/ adjective referring to histology

histological grade / h stəlɒd k(ə)l &re d/ noun a system of classifying tumours

according to how malignant they are histology /h stɒləd i/ noun the study of the

anatomy of tissue cells and minute cellular structure

histolysis /h stɒləs s/ noun the disintegration of tissue

histolytica / h stə l t kə/ Entamoeba his-

tolytica

histoplasmosis / h stəυpl z məυs s/ noun a lung disease caused by infection with the fungus Histoplasma

history / h st(ə)ri/ noun the background information on someone’s illness. case history, medical history to take a patient’s history to ask someone to tell what has happened to them in their own words on being admitted to hospital

‘…these children gave a typical history of exerciseinduced asthma’ [Lancet]

‘…the need for evaluation of patients with a history of severe heart disease’ [Southern Medical Journal]

histotoxic / h stəυ tɒks k/ adjective referring to a substance which is poisonous to tissue

HIV abbr human immunodeficiency virus

‘HIV-associated dementia is characterized by psychomotor slowing and inattentiveness’ [British Journal of Nursing]

COMMENT: HIV is the virus which causes AIDS. Three strains of HIV virus have been identified: HIV-1, HIV-2 and HIV-3.

hives /ha vz/ noun same as urticaria (NOTE: Takes a singular verb.)

HIV-negative / e tʃ a vi ne&ət v/ adjective referring to someone who has been tested and shown not to have HIV

HIV-positive / e tʃ a vi pɒz t v/ adjective referring to someone who has been tested and shown to have HIV

HLA abbr human leucocyte antigen

HLA system / e tʃ el e s stəm/ noun a system of HLA antigens on the surface of cells which need to be histocompatible to allow transplants to take place

COMMENT: HLA-A is the most important of the antigens responsible for rejection of transplants.

HMO abbr US Health Maintenance Organization

hoarse /hɔ s/ adjective referring to a voice which is harsh and rough

hoarseness / hɔ snəs/ noun a harsh and rough sound of the voice, often caused by laryngitis

hobnail liver / hɒbne l l və/ noun same as atrophic cirrhosis

Hodgkin’s disease / hɒd k nz d zi z/ noun a malignant disease in which the lymph glands are enlarged and there is an increase in the lymphoid tissues in the liver, spleen and bone marrow. It is frequently fatal if not treated early. [Described 1832. After Thomas Hodgkin (1798–1866), British physician.]

hoist /hɔ st/ noun a device with pulleys and wires for raising a bed or a patient

hole in the heart / həυl n ðə hɑ t/ noun same as septal defect (informal)

Holger-Nielsen method / hɒl&ə n lsənmeθəd/ noun a formerly used method of giv-

ing artificial respiration by pressing a person’s back and raising their arms backwards holism / həυl z(ə)m/ noun the theory that all of a person’s physical, mental and social conditions should be considered in the treatment of his or her illness

holistic /həυ l st k/ adjective referring to a method of treatment involving all of someone’s mental and family circumstances rather than just dealing with the condition from which he or she is suffering

holistic care /həυ l st k keə/ noun the care and treatment of a whole person rather than just of his or her medical symptoms

holo- /hɒləυ/ prefix entire, complete

holocrine / hɒləkr n/ adjective referring to a gland where the secretions are made up of disintegrated cells of the gland itself

Homans’ sign / həυmənz sa n/ noun pain in the calf when the foot is bent back, a sign of deep-vein thrombosis [Described 1941. After John Homans (1877–1954), Professor of Clinical Surgery at Harvard, USA.]

homeo- /həυmiəυ/ prefix like or similar

homeopathic / həυmiə p θ k/, homoeopathic /həυmiə p θ k/ adjective 1. referring to homeopathy a homeopathic clinic She is having a course of homeopathic treatment.

2. referring to a drug which is given in very small quantities

homeopathist / həυmi ɒpəθ st/, homoeopathist /həυmi ɒpəθ st/ noun a person who

practises homeopathy

homeopathy / həυmi ɒpəθi/, homoeopathy

/həυmi ɒpəθi/ noun the treatment of a condition by giving the person very small quantities of a substance which, when given to a healthy person, would cause symptoms like those of the condition being treated. Compare allopathy

homeostasis / həυmiəυ ste s s/ noun the process by which the functions and chemistry of a cell or internal organ are kept stable, even when external conditions vary greatly homo- /həυməυ/ prefix the same

homoeo- /həυmiəυ/ prefix another spelling of homeo- (used before vowels) homogenise /hə mɒd əna z/, homogenize verb to give something a uniform nature homograft / hɒmə&rɑ ft/ noun the graft of an organ or tissue from a donor to a recipient of the same species, e.g. from one person to another. Also called allograft. Compare heterograft

homolateral / hɒmə l t(ə)rəl/ adjective same as ipsilateral

homologous /hɒ mɒlə&əs/ adjective 1. of the same type 2. referring to chromosomes which form a pair

homonymous /hə mɒn məs/ adjective affecting the two eyes in the same way

homonymous hemianopia /hə mɒn məs hemiə nəυpiə/ noun a condition in which the

same half of the field of vision is lost in each eye

homoplasty / həυməυpl sti/ noun surgery to replace lost tissues by grafting similar tissues from another person

homosexual / həυməυ sekʃuəl/ adjective referring to homosexuality noun a person who is sexually attracted to people of the same sex. Compare bisexual, heterosexual (NOTE: Although homosexual can apply to both males and females, it is commonly used for males only, and lesbian is used for females.) homosexuality / həυməυsekʃu l ti/ noun sexual attraction to people of the same sex or sexual relations with people of the same sex homozygous / həυməυ za &əs/ adjective having two identical versions of a specific gene. Compare heterozygous

hook /hυk/ noun a surgical instrument with a bent end used for holding structures apart in operations

hookworm / hυkw! m/ noun a parasitic worm

hookworm disease / hυkw! m d zi z/ noun ancylostomiasis

hordeolum /hɔ di ələm/ noun an infection of the gland at the base of an eyelash. Also called stye

horizontal / hɒr zɒnt(ə)l/ adjective lying flat or at a right angle to the vertical horizontal fissure / hɒr zɒnt(ə)l f ʃə/ noun ANAT a horizontal groove between the superior and middle lobes of a lung. See illustration at LUNGS in Supplement

horizontal plane / hɒr zɒnt(ə)l ple n/ adjective same as transverse plane. see illustration at ANATOMICAL TERMS in Supplement

hormonal /hɔ məυn(ə)l/ adjective referring to hormones

hormone / hɔ məυn/ noun a substance which is produced by one part of the body, especially the endocrine glands and is carried to another part of the body by the bloodstream where it has particular effects or functions

hormone replacement therapy / hɔ məυn r ple smənt θerəpi/, hormone therapy / hɔ məυn θerəpi/ noun 1. treatment for some-

one whose endocrine glands have been removed 2. treatment to relieve the symptoms of the menopause by supplying oestrogen and reducing the risk of osteoporosis Abbr HRT

horn /hɔ n/ noun 1. (in humans) tissue which grows out of an organ 2. (in humans) one of the H-shaped limbs of grey matter seen in a crosssection of the spinal cord 3. (in humans) an extension of the pulp chamber of a tooth towards the cusp

Horner’s syndrome / hɔ nəz s ndrəυm/ noun a condition caused by paralysis of the sympathetic nerve in one side of the neck, making the eyelids hang down and the pupils contract [Described 1869. After Johann Friedrich Horner (1831–86), Professor of Ophthalmology in Zürich, Switzerland.]

horny / hɔ ni/ adjective referring to skin which is very hard (NOTE: For terms referring to horny tissue, see words beginning with kerat-, kerato-.)

horseshoe kidney / hɔ sʃu k dni/ noun a congenital condition of the kidney, where sometimes the upper but usually the lower parts of both kidneys are joined together

Horton’s syndrome / hɔ t(ə)nz s n drəυm/ noun a severe headache, often with constant pain around one eye, which starts usually within a few hours of going to sleep. It is caused by the release of histamine in the body. [After Bayard Taylor Horton (b. 1895), US physician]

hose /həυz/ noun 1. a long rubber or plastic tube 2. support hose

hospice / hɒsp s/ noun a hospital which offers palliative care for terminally ill people

hospital / hɒsp t(ə)l/ noun a place where sick or injured people are looked after hospital bed 1. a special type of bed used in hospitals, usually adjustable in many ways for the comfort of the patient A hospital bed is needed if the patient has to have traction. 2. a place in a hospital which can be occupied by a patient There will be no reduction in the number of hospital beds.

hospital-acquired infection / hɒsp t(ə)l əkwa əd n fekʃən/ noun a disease caught

during a stay in hospital

Hospital Activity Analysis / hɒsp t(ə)lk t v ti ə n ləs s/ noun a regular detailed

report on patients in hospitals, including information about treatment, length of stay and outcome

hospital care / hɒsp t(ə)l keə/ noun treatment in a hospital

hospital chaplain / hɒsp t(ə)l tʃ pl n/ noun a religious minister attached to a hospital, who visits and comforts patients and their families and gives them the sacraments if necessary

hospital corner / hɒsp t(ə)l kɔ nə/ noun a way of folding the overlapping bedding at each corner of a bed that keeps it tight hospital doctor / hɒsp t(ə)l dɒktə/ noun a doctor who works only in a hospital and does not receive people in his or her own surgery hospital gangrene / hɒsp t(ə)l & ŋ&ri n/ noun gangrene caused by insanitary hospital conditions

hospital infection / hɒsp t(ə)l n fekʃən/ noun an infection which someone gets during a hospital visit, or one which develops among hospital staff

COMMENT: Hospital infection is an increasingly common problem due to growing antimicrobial resistance and inappropriate antibiotic use. Strains of bacteria such as MRSA have evolved which seem to be more easily transmitted between patients and are difficult to treat.

hospitalisation / hɒsp t(ə)la ze ʃ(ə)n/, hospitalization noun the act of sending someone to hospital The doctor recommended immediate hospitalisation.

hospitalise / hɒsp t(ə)la z/, hospitalize verb to send someone to hospital He is so ill that he has had to be hospitalised.

hospital orderly / hɒsp t(ə)l ɔ dəli/ noun a person who does heavy work in a hospital, such as wheeling patients into the operating theatre or moving equipment about

hospital trust / hɒsp t(ə)l tr"st/ noun same as self-governing hospital

host /həυst/ noun a person or animal on which a parasite lives

hot /hɒt/ adjective very warm or having a high temperature

hot flush / hɒt fl"ʃ/ noun a condition in menopausal women, in which the woman becomes hot and sweats, and which is often accompanied by redness of the skin

hotpack / hɒtp k/ noun a cloth bag or a pad filled with gel or grains which can be heated and applied to the skin to relieve pain or stiffness

hot wax treatment / hɒt w ks tri tmənt/ noun a treatment for arthritis in which the joints are painted with hot liquid wax

hourglass contraction / aυə&lɑ s kəntr kʃən/ noun a condition in which an organ such as the stomach is constricted in the centre hourglass stomach / aυə&lɑ s st"mək/ noun a condition in which the wall of the stomach is pulled in so that it is divided into two cavities, cardiac and pyloric

hourly / aυəli/ adjective, adverb happening every hour

houseman / haυsmən/ noun same as house officer

house mite /haυs ma t/, house dust mite / haυs d"st ma t/ noun a tiny insect living

mainly in bedding and soft furnishings, that can cause an allergic reaction

house officer / haυs ɒf sə/ noun a doctor who works in a hospital as a house surgeon or house physician during the final year of training before registration by the General Medical Council (NOTE: The US term is intern.)

HPRT noun an enzyme that is lacking in children, usually boys, who have Lesch-Nyhan disease. Full form hypoxanthine phosphoribosyl transferase. Also called HGPRT (hypoxanthine guanine phosphoribosyl transferase)

HPV abbr human papillomavirus

HRT abbr hormone replacement therapy

Huhner’s test / hu nəz test/ noun a test carried out several hours after sexual intercourse to determine the number and motility of spermatozoa [After Max Huhner (1873–1947), US urologist]

human / hju mən/ adjective referring to any man, woman or child noun a person Most animals are afraid of humans.

human anatomy / hju mən ə n təmi/ noun the structure, shape and functions of the human body

human being / hju mən bi ŋ/ noun a person

human chorionic gonadotrophin /

hju mən kɔ ri ɒn k &əυnədə trəυf n/ noun a hormone produced by the placenta, which suppresses the mother’s usual menstrual cycle during pregnancy. It is found in the urine during pregnancy, and can be given by

injection to encourage ovulation and help a

woman to become pregnant. Abbr hCG human crutch / hju mən kr"tʃ/ noun a

method of helping an injured person to walk, where they rest one arm over the shoulders of the person helping

human immunodeficiency virus /

hju mən mjυnəυd f ʃ(ə)nsi va rəs/ noun a virus which causes AIDS. Abbr HIV

human leucocyte antigen / hju mən lu kəsa t nt d (ə)n/ noun any of the sys-

tem of antigens on the surface of cells which need to be histocompatible to allow transplants to take place. Abbr HLA. HLA system human nature / hju mən ne tʃə/ noun the general behavioural characteristics of human beings

human papillomavirus / hju mən p p ləυmə va rəs/ noun a virus that causes geni-

tal warts in humans. Abbr HPV

humectant /hju mektənt/ adjective able to absorb or retain moisture noun a substance that can absorb or retain moisture, e.g. a skin lotion

humeroulnar joint / hju mərəυ "lnə d ɔ nt/ noun part of the elbow joint, where the trochlea of the humerus and the trochlear

notch of the ulna move next to each other humerus / hju mərəs/ noun the top bone in

the arm, running from the shoulder to the elbow (NOTE: The plural is humeri.)

humid / hju m d/ adjective damp, containing moisture vapour

humoral / hju mərəl/ adjective relating to human body fluids, in particular blood serum humour / hju mə/, humor noun a fluid in the

body

hunchback / h"ntʃb k/ noun kyphosis hunger / h"ŋ&ə/ noun a need to eat hunger pains / h"ŋ&ə pe ns/ plural noun

pains in the abdomen when a person feels hungry, sometimes a sign of a duodenal ulcer

Hunter’s syndrome / h"ntəz s ndrəυm/ noun an inherited disorder caused by an enzyme deficiency, which leads to learning difficulties

Huntington’s chorea / h"nt ŋtənz kɔ ri ə/ noun a progressive hereditary disease which affects adults, where the outer layer of the brain degenerates and the person makes involuntary jerky movements and develops progressive dementia [Described 1872. After George Sumner Huntington (1850–1916), US

physician.]

Hurler’s syndrome / h! ləz s ndrəυm/ noun same as gargoylism [Described 1920. After Gertrud Hurler, German paediatrician.] hurt /h! t/ noun 1. emotional pain 2. a painful area (used by children) She has a hurt on her knee. verb 1. to have pain He’s hurt his hand. 2. to cause someone pain His arm is

hurting so much he can’t write. She fell down and hurt herself. (NOTE: hurting – hurt)

adjective 1. feeling physical pain He was slightly hurt in the car crash. Two players got hurt in the football game. 2. feeling emotional pain Her parents’ divorce hurt her deeply.

husky / h"ski/ adjective slightly hoarse

Hutchinson’s tooth / h"tʃ nsənz tu θ/ noun a narrow upper incisor tooth, with notches along the cutting edge, a symptom of congenital syphilis but also occurring naturally

(NOTE: The plural is Hutchinson’s teeth.) [After Sir Jonathan Hutchinson (1828–1913), British surgeon]

hyal- /ha əl/ prefix like glass (used before vowels)

hyalin / ha əl n/ noun a transparent substance produced from collagen and deposited around blood vessels and scars when some tissues degenerate

hyaline / ha əl n/ adjective nearly transparent like glass

hyaline cartilage / ha əl n kɑ t l d / noun a type of cartilage found in the nose, larynx and joints. It forms most of the skeleton of the fetus. See illustration at CARTILAGINOUS JOINT in Supplement

hyaline membrane disease / ha əl n membre n d zi z/ noun same as respiratory

distress syndrome

hyalitis / ha ə la t s/ noun inflammation of the vitreous humour or the hyaloid membrane in the eye. Also called vitritis

hyaloid membrane / ha əlɔ d membre n/ noun a transparent membrane round the vitreous humour in the eye

hyaluronic acid / ha əlυrɒn k s d/ noun a substance which binds connective tissue and is found in the eyes

hyaluronidase / ha əlυ rɒn de z/ noun an enzyme which destroys hyaluronic acid hybrid / ha br d/ noun an organism that is a result of a cross between individuals that are not genetically the same as each other HYCOSY abbr hysterosalpingo-contrast sonography

hydatid / ha dət d/ noun any cyst-like structure

hydatid cyst / ha dət d s st/ noun the larval form of the tapeworms of the genus Echinococcus

hydatid disease / ha dət d d zi z/, hydatidosis / ha dət dəυs s/ noun an infection, usually in the lungs or liver, caused by expanding hydatid cysts that destroy the tissues of the infected organ

hydatid mole / ha dət d məυl/ noun an abnormal pregnancy from a pathologic ovum, resulting in a mass of cysts shaped like a bunch of grapes

hydr- /ha dr/ prefix same as hydro- (used before vowels)

hydraemia /ha dri miə/ noun an excess of

water in the blood

hydragogue / ha drə&ɒ&/ noun a laxative or substance which produces watery faeces hydralazine /ha dr ləzi n/ noun a drug that lowers blood pressure. People usually receive it in combination with other drugs that in-

crease the output of urine.

hydramnios /ha dr mniɒs/ noun an unusually large amount of amniotic fluid sur-

rounding the fetus

hydrarthrosis / ha drɑ θrəυs s/ noun swelling caused by excess synovial liquid at a joint

hydrate / ha dre t/ verb to give water to someone so as to re-establish or maintain fluid balance noun a chemical compound containing water molecules that can usually be driven off by heat without altering the compound’s structure

hydro- /ha drəυ/ prefix referring to water hydroa /ha drəυə/ noun an eruption of small

itchy blisters, e.g. those caused by sunlight hydrocalycosis / ha drəυ k l kəυs s/

noun same as caliectasis

hydrocele / ha drəυsi l/ noun the collection of watery liquid found in a cavity such as the

scrotum

hydrocephalus / ha drəυ kefələs/ noun an excessive quantity of cerebrospinal fluid in the brain

hydrochloric acid /ha drəυ klɒr k s d/ noun an acid found in the gastric juices which

helps to break apart the food

hydrocolloid strip / ha drəυkɒlɔ d str p/ noun a waterproof gel dressing that seals a wound, retaining moisture and preventing ac-

cess to germs and dirt

hydrocolpos / ha drəυ kɒlpəs/ noun a cyst in the vagina containing clear fluid hydrocortisone / ha drəυ kɔ t zəυn/ noun a steroid hormone secreted by the adrenal cortex or produced synthetically, used in the treatment of rheumatoid arthritis and inflammatory

and allergic conditions

hydrocyanic acid / ha drəυsa n k s d/

noun an acid which forms cyanide. Abbr HCN hydrogen / ha drəd ən/ noun a chemical el-

ement, a gas which combines with oxygen to form water, and with other elements to form acids, and is present in all animal tissue (NOTE:

The chemical symbol is H.)

hydrogen peroxide / ha drəd ən pə rɒk

sa d/ noun a solution used as a disinfectant hydrolysis /ha drɒləs s/ noun the breaking

down of a chemical compound when it reacts with water to produce two or more different compounds, as in the conversion of starch to glucose

hydroma /ha drəυmə/ noun same as hygroma

hydrometer /ha drɒm tə/ noun an instrument which measures the density of a liquid hydromyelia / ha drəυma i liə/ noun a condition in which fluid swells the central canal of the spinal cord

hydronephrosis / ha drəυne frəυs s/ noun swelling of the pelvis of a kidney caused by accumulation of water due to infection or a kidney stone blocking the ureter

hydropathy /ha drɒpəθi/ noun the treatment of injuries or disease by bathing in water or drinking mineral waters

hydropericarditis / ha drəυ perikɑ da t s/, hydropericardium / ha drəυ peri kɑ diəm/

noun an accumulation of liquid round the heart hydroperitoneum / ha drəυ per tə ni əm/ noun a build-up of fluid in the peritoneal cavity

(NOTE: The plural is hydroperitoneums or hy-

droperitonea.)

hydrophobia / ha drə fəυbiə/ noun same as rabies

COMMENT: Hydrophobia affects the mental balance, and the symptoms include difficulty in breathing or swallowing and a horror of water.

hydropneumoperitoneum / ha drəυnju məυ per tə ni əm/ noun a condition in

which watery fluid and gas collect in the peritoneal cavity

hydropneumothorax / ha drəυ nju məυ θɔ r ks/ noun a condition in which watery fluid and gas collect in the pleural cavity

(NOTE: The plural is hydropneumothoraxes or

hydropneumothoraces.)

hydrops / ha drɒps/ noun same as oedema

(NOTE: The plural is hydropses.) hydrorrhoea / ha drəυ ri ə/ noun a discharge of watery fluid (NOTE: The US spelling is

hydrorrhea.)

hydrosalpinx / ha drəυ s lp ŋks/ noun an occasion when watery fluid collects in one or both of the Fallopian tubes, causing swelling

(NOTE: The plural is hydrosalpinges.) hydrotherapy / ha drəυ θerəpi/ noun a type of physiotherapy involving treatment in water, where people are put in hot baths or are encouraged to swim

hydrothorax / ha drəυ θɔ r ks/ noun the collection of liquid in the pleural cavity hydrotubation / ha drəυtju be ʃ(ə)n/ noun an act of putting a fluid through the neck of the uterus and the Fallopian tubes under pressure to check whether the tubes are blocked

hydroureter / ha drəυju ri tə/ noun a condition in which water or urine collect in the ureter because it is blocked

hydroxide /ha drɒksa d/ noun a chemical compound containing a hydroxyl group

hydroxyproline /ha drɒksi prəυli n/ noun an amino acid present in some proteins, especially in collagen

hygiene / ha d i n/ noun 1. the procedures and principles designed to keep things clean and to keep conditions healthy Nurses have to maintain a strict personal hygiene. 2. the science of health

hygienic /ha d i n k/ adjective 1. clean

Don’t touch the food with dirty hands – it isn’t hygienic. 2. producing healthy conditions hygienist / ha d i n st/ noun a person who specialises in hygiene and its application hygr- /ha &r/ prefix same as hygro- (used before vowels)

hygro- /ha &rəυ/ prefix relating to moisture hygroma /ha &rəυmə/ noun a kind of cyst which contains a thin fluid

hymen / ha men/ noun a membrane which partially covers the vaginal passage in a female who has never had sexual intercourse hymenectomy / ha mə nektəmi/ noun 1. the surgical removal of the hymen, or an operation to increase the size of the opening of the hymen 2. the surgical removal of any membrane

hymenotomy / ha mə nɒtəmi/ noun an incision of the hymen during surgery

hyo- /ha əυ/ prefix relating to the hyoid bone hyoglossus / ha əυ &lɒsəs/ noun a muscle which is attached to the hyoid bone and depresses the tongue

hyoid / ha ɔ d/ adjective relating to the hyoid

bone

hyoid bone / ha ɔ d bəυn/ noun a small U- shaped bone at the base of the tongue hyoscine / ha əυsi n/ noun a drug used as a sedative, in particular for treatment of motion sickness

hyp- /ha p/ prefix same as hypo- (used before vowels)

hypaemia /ha pi miə/ noun an insufficient amount of blood in the body

hypalgesia / ha p l d i ziə/ noun low sensitivity to pain

hyper- /ha pə/ prefix higher or too much. Op-

posite hypo-

hyperacidity / ha pərə s d ti/ noun the production of more acid in the stomach than is usual. Also called acidity, acid stomach hyperacousia / ha pərə kju ziə/ noun same as hyperacusis

hyperactive /ha pər kt v/ adjective very or unusually active

hyperactivity /ha pər k t vəti/ noun a condition in which something or someone, e.g. a gland or a child, is too active

hyperacusis / ha pərə kju s s/ noun a condition in which someone is very sensitive to sounds