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Lungs, Breathing and Respiration Glossary

Terms used to explain Lungs, Breathing and Respiration can sometimes be confusing. To help you fully understand the articles and features related to this very important health topic, we have compiled a glossary of terms that can help.

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Pronunciation: \-ˌkärs-ən-ˈō-mə\

Function: noun
pl -mas
also -ma*ta
Pronunciation: \-mət-ə\
: a malignant tumor originating in glandular epithelium


Pronunciation: \ˈal-ər-jən\
Function: noun
1: a substance that induces allergy <inhaled allergens> <a suspected food allergen>


Pronunciation: \ˌant-i-ˈhis-tə-ˌmēn, ˌan-ˌtī-, -mən\

Function: adjective
: tending to block or counteract the physiological action of histamine <human blood lacks antihistamine[1] activity>


Pronunciation: \-ˈprōt-ē-ˌās, -ˌāz\
Function: noun
1: a substance that inhibits the enzymatic activity of a protease


Pronunciation: \as-ˈbes-təs, az-\

Function: noun
: any of several minerals that readily separate into long flexible fibers, that have been implicated as causes of certain cancers, and that have been used esp. formerly as fireproof insulating materials


Pronunciation: \ˈaz-mə\
Function: noun
1: a chronic lung disorder that is marked by recurring episodes of airway obstruction (as from bronchospasm) manifested by labored breathing accompanied esp. by wheezing and coughing and by a sense of constriction in the chest, and that is triggered by hyperreactivity to various stimuli (as allergens or rapid change in air temperature)

Learn more: Managing Asthma

Pronunciation: \ˈat-ə-pē\

Function: noun
pl -pies
: a prob. hereditary allergy characterized by symptoms (as asthma, hay fever, or hives) produced upon exposure esp. by inhalation to the exciting environmental antigen

B Cell

B cell
Function: noun
: any of the lymphocytes that have antigen-binding antibody molecules on the surface, that comprise the antibody-secreting plasma cells when mature, and that in mammals differentiate in the bone marrow —called also B lymphocyte, compare t cell


Pronunciation: \ˈbī-ˌäp-sē\

Function: noun
pl -sies
: the removal and examination of tissue, cells, or fluids from the living body


Pronunciation: \ˈbräŋ-kē-əl\

Function: adjective
: of or relating to the bronchi or their ramifications in the lungs

Bronchial Tube

bronchial tube
Function: noun
: a primary bronchus; also: any of its branches


Pronunciation: \brän-ˈkīt-əs, bräŋ-\
Function: noun
1: acute or chronic inflammation of the bronchial tubes; also: a disease marked by this


Pronunciation: \-dī-ˈlāt-ər, -ˈdī-ˌlāt-\
Function: adjective
1: relating to or causing expansion of the bronchial air passages <bronchodilator[1] activity> <bronchodilator[1] drugs>

Learn more: Breathe Easier

Pronunciation: \brän-ˈkäs-kə-pē, bräŋ-\

Function: noun
pl -pies
: the use of a bronchoscope in the examination or treatment of the bronchi


Function: abbreviation
chronic obstructive pulmonary disease


Pronunciation: \kär-ˈsin-ə-jən, ˈkärs-ən-ə-ˌjen\

Function: noun
: a substance or agent causing cancer


Pronunciation: \-ˈther-ə-pē\

Function: noun
pl -pies
: the use of chemical agents in the treatment or control of disease or mental disorder

Cor Pulmonale

cor pul*mo*na*le
Pronunciation: \ˌkor-ˌpul-mə-ˈnäl-ē, -ˌpəl-, -ˈnal-\
Function: noun
1: disease of the heart characterized by hypertrophy and dilatation of the right ventricle and secondary to disease of the lungs or their blood vessels


Pronunciation: \ˌkort-i-kō-ˈsti(ə)r-ˌoid also -ˈste(ə)r-\

Function: noun
: any of various adrenal-cortex steroids (as corticosterone, cortisone, and aldosterone) that are divided on the basis of their major biological activity into glucocorticoids and mineralocorticoids

Cystic Fibrosis

Function: noun
1: a hereditary disease prevalent esp. in Caucasian populations that appears usu. in early childhood, is inherited as an autosomal recessive monogenic trait, involves functional disorder of the exocrine glands, and is marked esp. by faulty digestion due to a deficiency of pancreatic enzymes, by difficulty in breathing due to mucus accumulation in airways, and by excessive loss of salt in the sweat —called also fibrocystic disease of the pancreas, mucoviscidosi


Pronunciation: \ˈdan-dər\

Function: noun
: see: dandruff; specif: minute scales from hair, feathers, or skin that may act as allergens


Pronunciation: \ˌdē-kən-ˈjes-tənt\
Function: noun
1: an agent that relieves congestion (as of mucous membranes)


Pronunciation: \ˈdī-ə-ˌfram\
Function: noun
1: a body partition of muscle and connective tissue; specif: the partition separating the chest and abdominal cavities in mammals see pelvic diaphragm urogenital diaphragm
2: a device that limits the aperture of a lens or optical system
3: a molded cap usu. of thin rubber fitted over the uterine cervix to act as a mechanical contraceptive barrier

Dust Mite

dust mite
Function: noun
: any of various mites (esp. family Pyroglyphidae) implicated in human allergic reactions to dust; esp: see: house-dust mite


Pronunciation: \ig-ˈzē-mə, ˈeg-zə-mə, ˈek-sə-\

Function: noun
: an inflammatory condition of the skin characterized by redness, itching, and oozing vesicular lesions which become scaly, crusted, or hardened


Pronunciation: \i-ˈlas-tən\
Function: noun
1: a protein that is similar to collagen and is the chief constituent of elastic fibers


Pronunciation: \i-ˌlim-ə-ˈnā-shən\

Function: noun

1: the act of discharging or excreting waste products or foreign substances from the body
2eliminationspl: bodily discharges including urine, feces, and vomit
3: the removal from a molecule of the constituents of a simpler molecule <ethylene is formed by the elimination of water from ethanol>


Pronunciation: \ˌem(p)-fə-ˈzē-mə, -ˈsē-\
Function: noun
1: a condition characterized by air-filled expansions in interstitial or subcutaneous tissues; specif: a condition of the lung that is marked by distension and eventual rupture of the alveoli with progressive loss of pulmonary elasticity, that is accompanied by shortness of breath with or without cough, and that may lead to impairment of heart action


Pronunciation: \ˌeks-(h)ə-ˈlā-shən\

Function: noun

1: the action of forcing air out of the lungs
2: something (as the breath) that is exhaled or given off

Gene Therapy

gene therapy
Function: noun
: the insertion of usu. genetically altered genes into cells esp. to replace defective genes in the treatment of genetic disorders or to provide a specialized disease-fighting function (as the destruction of tumor cells)


Pronunciation: \ˈhep-ə\

Function: adjective
Etymology: high efficiency particulate air
: being, using, or containing a filter usu. designed to remove 99.97% of airborne particles measuring 0.3 microns or greater in diameter passing through it <HEPA filters> <HEPA vacuum cleaners>

Hay Fever

hay fever
Pronunciation: \ˈhā-ˌfē-vər\

Function: noun
: an acute allergic reaction to pollen that is usu. seasonal and is marked by sneezing, nasal discharge and congestion, and itching and watering of the eyes —called also pollinosis


Pronunciation: \ˈhis-tə-ˌmēn, -mən\

Function: noun
: a compound C5H9N3 esp. of mammalian tissues that causes dilatation of capillaries, contraction of smooth muscle, and stimulation of gastric acid secretion, that is released during allergic reactions, and that is formed by decarboxylation of histidine


Pronunciation: \ˈhīvz\

Function: noun plural but singular or plural in construction
: an allergic disorder marked by raised edematous red patches of skin or mucous membrane and usu. by intense itching and caused by contact with a specific precipitating factor (as a food, drug, or inhalant) either externally or internally —called also urticaria


Pronunciation: \hyü-ˈmid-ə-ˌfī(-ə)r, yü-\
Function: noun
1: a device for supplying or maintaining humidity


Pronunciation: \ˈhī-ˌjēn also hī-ˈ\

Function: noun

1: a science of the establishment and maintenance of health see industrial hygiene mental hygiene
2: conditions or practices (as of cleanliness) conducive to health


Pronunciation: \ˌhī-pə-rin-ˈflā-shən\
Function: noun
1: excessive inflation (as of the lungs)


Pronunciation: \-ˈther-ə-pē\

Function: noun
pl -pies
: treatment of or prophylaxis against disease by attempting to produce active or passive immunity —called also immune therapy


Pronunciation: \ˌin-flə-ˈmā-shən\
Function: noun
1: a local response to cellular injury that is marked by capillary dilatation, leukocytic infiltration, redness, heat, pain, swelling, and often loss of function and that serves as a mechanism initiating the elimination of noxious agents and of damaged tissue


Pronunciation: \in-ˈhā-lər\
Function: noun
1: a device by means of which usu. medicinal material is inhaled compare inhalator

Learn more: Using Inhalers

Pronunciation: \ˈir-ə-tənt\

Function: adjective
: causing irritation; specif: tending to produce inflammation


Pronunciation: \ˌlü-kə-ˈtrī-ˌēn\

Function: noun
: any of a group of eicosanoids that are generated in basophils, mast cells, macrophages, and human lung tissue by lipoxygenase-catalyzed oxygenation esp. of arachidonic acid and that participate in allergic responses (as bronchoconstriction in asthma) see slow-reacting substance of anaphylaxis


Pronunciation: \lō-ˈbek-tə-mē\

Function: noun
pl -mies
: surgical removal of a lobe of an organ (as a lung) or gland (as the thyroid); specif: excision of a lobe of the lung compare lobotomy

Mast Cell

mast cell
Pronunciation: \ˈmast-\

Function: noun
: a granulocyte that occurs esp. in connective tissue and has basophilic granules containing substances (as histamine and heparin) which mediate allergic reactions


Pronunciation: \ˌmez-ə-ˌthē-lē-ˈō-mə, ˌmēz-, ˌmēs-, ˌmes-\

Function: noun
pl -mas
also -ma*ta
Pronunciation: \-mət-ə\
: a tumor derived from mesothelial tissue (as that lining the peritoneum or pleura)


Pronunciation: \ˈmyü-kəs\

Function: noun
: a viscid slippery secretion that is usu. rich in mucins and is produced by mucous membranes which it moistens and protects


Function: noun
: see: atomizer; specif: an atomizer equipped to produce an extremely fine spray for deep penetration of the lungs


Pronunciation: \ˈäk-si-jən\
Function: noun
1: a colorless tasteless odorless gaseous element that constitutes 21 percent of the atmosphere and is found in water, in most rocks and minerals, and in numerous organic compounds, that is capable of combining with all elements except the inert gases, that is active in physiological processes, and that is involved esp. in combustion processes 

Learn more: Safe Oxygen Tips
Patch Test

patch test
Function: noun
: a test for determining allergic sensitivity that is made by applying to the unbroken skin small pads soaked with the allergen to be tested and that indicates sensitivity when irritation develops at the point of application compare intradermal test prick test scratch test

Peak Flow Meter

peak flow meter
Pronunciation: \ˌpēk-ˈflō-\

Function: noun
: a device that measures the maximum rate of air flow out of the lungs during forced expiration and that is used esp. for monitoring lung capacity of individuals with asthma (as to indicate bronchial narrowing) —called also peak expiratory flow meter

Peripheral Neuropathy

peripheral neuropathy
Function: noun
: a disease or degenerative state (as polyneuropathy) of the peripheral nerves in which motor, sensory, or vasomotor nerve fibers may be affected and which is marked by muscle weakness and atrophy, pain, and numbness

Plasma Cell

plasma cell
Function: noun
: a lymphocyte that is a mature antibody-secreting B cell


Pronunciation: \n(y)u-ˈmō-nyə\
Function: noun
1: a disease of the lungs that is characterized esp. by inflammation and consolidation of lung tissue followed by resolution, is accompanied by fever, chills, cough, and difficulty in breathing, and is caused chiefly by infection see bronchopneumonia lobar pneumonia primary atypical pneumonia


Pronunciation: \ˈpäl-ən\

Function: noun
: a mass of male spores in a seed plant appearing usu. as a fine dust


Pronunciation: \ˈpred-nə-ˌsōn also -ˌzōn\

Function: noun
: a glucocorticoid C21H26O5 that is a dehydrogenated analog of cortisone and is used as an anti-inflammatory agent, as an antineoplastic agent, and as an immunosuppressant

Prick Test

prick test
Pronunciation: \ˈprik-\

Function: noun
: a test for allergic susceptibility made by placing a drop of the allergy-producing substance on the skin and making breaks in the skin by lightly pricking the surface (as with a pin) compare intradermal test patch test scratch test


Pronunciation: \ˌres-pə-ˈrā-shən\
Function: noun
1 a: the movement of respiratory gases (as oxygen and carbon dioxide) into and out of the lungs
b: a single complete act of breathing <30 respirations per minute>
2: the physical and chemical processes (as breathing and diffusion) by which an organism supplies its cells and tissues with the oxygen needed for metabolism and relieves them of the carbon dioxide formed in energy-producing reactions
3: see: cellular respiration


Pronunciation: \rī-ˈnīt-əs\

Function: noun
pl -nit*i*des
Pronunciation: \-ˈnit-ə-ˌdēz\
: inflammation of the mucous membrane of the nose marked esp. by rhinorrhea, nasal congestion and itching, and sneezing; also: any of various conditions characterized by rhinitis see allergic rhinitis rhinitis medicamentosa rhinitis sicca vasomotor rhinitis

Secondhand Smoke

sec*ond*hand smoke
Pronunciation: \ˌsek-ən(d)-ˌhan(d)-\

Function: noun
: tobacco smoke that is exhaled by a smoker or is given off by burning tobacco (as of a cigarette) and is inhaled by persons nearby —called also passive smoke


Pronunciation: \ˈsp(y)üt-əm\

Function: noun
pl spu*ta
Pronunciation: \-ə\
: the matter discharged from the air passages in diseases of the lungs, bronchi, or upper respiratory tract that contains mucus and often pus, blood, fibrin, or bacterial products


Pronunciation: \ˈsti(ə)r-ˌoid also ˈste(ə)r-\

Function: noun
: any of numerous natural or synthetic compounds containing a 17-carbon 4-ring system and including the sterols and various hormones and glycosides see anabolic steroid


Pronunciation: \thē-ˈäf-ə-lən\

Function: noun
: a feebly basic bitter crystalline compound C7H8N4O2 that is present in small amounts in tea but is prepared chiefly by synthesis, that is isomeric with theobromine, and that is used in medicine often in the form of derivatives or in combination with other drugs esp. as a bronchodilator to relieve or prevent symptoms of asthma and bronchospasm associated with chronic bronchitis and emphysema


Pronunciation: \ˈhwēz, ˈwēz\

Function: intransitive verb
: to breathe with difficulty usu. with a whistling sound

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© 2011 Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Inc.

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