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Digestive System Glossary

Terms used to explain Digestive System 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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Alimentary Canal

alimentary canal
Function: noun
: the tubular passage that extends from mouth to anus, functions in digestion and absorption of food and elimination of residual waste, and includes the mouth, pharynx, esophagus, stomach, small intestine, and large intestine

Allergy

al*ler*gy
Pronunciation: \ˈal-ər-jē\


Function: noun
pl -gies

1: altered bodily reactivity (as hypersensitivity) to an antigen in response to a first exposure <his bee-venom allergy may render a second sting fatal>
2: exaggerated or pathological reaction (as by sneezing, respiratory embarrassment, itching, or skin rashes) to substances, situations, or physical states that are without comparable effect on the average individual
3: medical practice concerned with allergies

Amylase

am*y*lase
Pronunciation: \ˈam-ə-ˌlās, -ˌlāz\


Function: noun
: any of a group of enzymes (as amylopsin) that catalyze the hydrolysis of starch and glycogen or their intermediate hydrolysis products

Antacid

1ant*ac*id
Pronunciation: \(ˈ)ant-ˈas-əd\


Function: adjective
: tending to counteract acidity

Ascites

as*ci*tes
Pronunciation: \ə-ˈsīt-ēz\


Function: noun
pl ascites
: abnormal accumulation of serous fluid in the spaces between tissues and organs in the cavity of the abdomen —called also hydroperitoneum

Balance

bal*ance
Pronunciation: \ˈbal-ən(t)s\


Function: noun

1: an instrument for weighing
2: mental and emotional steadiness
3 a: the relation in physiology between the intake of a particular nutrient and its excretion used with positive when the nutrient is in excess of the bodily metabolic requirement and with negative when dietary inadequacy and withdrawal of bodily reserves is presentsee nitrogen balance water balance
b: the maintenance (as in laboratory cultures) of a population at about the same condition and level

Barium Enema

barium enema
Function: noun
: a suspension of barium sulfate injected into the lower bowel to render it radiopaque, usu. followed by injection of air to inflate the bowel and increase definition, and used in the radiographic diagnosis of intestinal lesions

Biliary

bil*i*ary
Pronunciation: \ˈbil-ē-ˌer-ē\


Function: adjective

1: of, relating to, or conveying bile <biliary stasis>
2: affecting the bile-conveying structures <biliary disorders>

Biopsy

1bi*op*sy
Pronunciation: \ˈbī-ˌäp-sē\


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

Blood Sugar

blood sugar
Function: noun
: the glucose in the blood; also: its concentration (as in milligrams per 100 milliliters)

Bowel

bow*el
Pronunciation: \ˈbau(-ə)l\



Function: noun
: see: intestine see: gut; also: one of the divisions of the intestines usu. used in pl. except in medical use<move your bowels> <surgery of the involved bowel>

Cancer

can*cer
Pronunciation: \ˈkan(t)-sər\


Function: noun

1: a malignant tumor of potentially unlimited growth that expands locally by invasion and systemically by metastasis
2: an abnormal state marked by a cancer

Carcinogen

car*cin*o*gen
Pronunciation: \kär-ˈsin-ə-jən, ˈkärs-ən-ə-ˌjen\


Function: noun
: a substance or agent causing cancer

Celiac Disease

celiac disease
Function: noun
: a chronic hereditary intestinal disorder in which an inability to absorb the gliadin portion of gluten results in the gliadin triggering an immune response that damages the intestinal mucosa —called also celiac sprue, gluten-sensitive enteropathy, nontropical sprue, sprue

Chemotherapy

che*mo*ther*a*py
Pronunciation: \-ˈther-ə-pē\


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

Cholestasis

cho*le*sta*sis
Pronunciation: \ˌkō-lə-ˈstā-səs, ˌkäl-ə-\


Function: noun
pl -sta*ses
Pronunciation: \-ˈstā-ˌsēz\
: a checking or failure of bile flow

Cirrhosis

cir*rho*sis
Pronunciation: \sə-ˈrō-səs\



Function: noun
pl -rho*ses
Pronunciation: \-ˌsēz\

: widespread disruption of normal liver structure by fibrosis and the formation of regenerative nodules that is caused by any of various chronic progressive conditions affecting the liver (as long-term alcohol abuse or hepatitis) see biliary cirrhosis

Colectomy

col*ec*to*my
Pronunciation: \kə-ˈlek-tə-mē, kō-\


Function: noun
pl -mies
: excision of a portion or all of the colon

Colitis

co*li*tis
Pronunciation: \kō-ˈlīt-əs, kə-\


Function: noun
: inflammation of the colon see ulcerative colitis

Colonoscopy

co*lo*nos*co*py
Pronunciation: \ˌkō-lə-ˈnäs-kə-pē, ˌkäl-ə-\


Function: noun
pl -pies
: endoscopic examination of the colon <transabdominal colonoscopy with a sigmoidoscope via colotomy>

Colorectal

co*lo*rec*tal
Pronunciation: \ˌkō-lə-ˈrek-təl, ˌkäl-ə-\


Function: adjective
: relating to or affecting the colon and the rectum <colorectal cancer>

Common Bile Duct

common bile duct
Function: noun
: the duct formed by the union of the hepatic and cystic ducts and opening into the duodenum —called also ductus choledochus

Condom

con*dom
Pronunciation: \ˈkän-dəm also ˈkən-\


Function: noun

1: a sheath commonly of rubber worn over the penis (as to prevent conception or venereal infection during coitus) —called also sheath
2: a device that is designed to be inserted into the vagina before coitus and that resembles in form and function the condom used by males

Constipation

con*sti*pa*tion
Pronunciation: \ˌkän(t)-stə-ˈpā-shən\


Function: noun
: abnormally delayed or infrequent passage of dry hardened feces

Corticosteroid

cor*ti*co*ste*roid
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

Diarrhea

di*ar*rhea
Function: noun
: abnormally frequent intestinal evacuations with more or less fluid stools

Diverticulitis

di*ver*tic*u*li*tis
Pronunciation: \-ˈlīt-əs\


Function: noun
: inflammation or infection of a diverticulum of the colon that is marked by abdominal pain or tenderness often accompanied by fever, chills, and cramping

Diverticulosis

di*ver*tic*u*lo*sis
Pronunciation: \-ˈlō-səs\


Function: noun
pl -lo*ses
Pronunciation: \-ˌsēz\
: an intestinal condition characterized by the presence of diverticula in the colon that is typically symptomless but may be marked by symptoms (as bleeding or constipation)

Duodenitis

du*o*de*ni*tis
Pronunciation: \d(y)u-ˌäd-ən-ˈīt-əs\


Function: noun
: inflammation of the duodenum

Duodenum

du*o*de*num
Pronunciation: \ˌd(y)ü-ə-ˈdē-nəm, d(y)u-ˈäd-ən-əm\


Function: noun
pl -de*na
Pronunciation: \-ˈdē-nə, -ən-ə\
or -de*nums
: the first, shortest, and widest part of the small intestine that in humans is about 10 inches (25 centimeters) long and that extends from the pylorus to the undersurface of the liver where it descends for a variable distance and receives the bile and pancreatic ducts and then bends to the left and finally upward to join the jejunum near the second lumbar vertebra

Dysentery

dys*en*tery
Pronunciation: \ˈdis-ən-ˌter-ē\


Function: noun
pl -ter*ies

1: a disease characterized by severe diarrhea with passage of mucus and blood and usu. caused by infection
2: see: diarrhea

Dysphagia

dys*pha*gia
Pronunciation: \dis-ˈfā-j(ē-)ə\


Function: noun
: difficulty in swallowing

Edema

ede*ma
Function: noun
pl -mas
also -ma*ta
Pronunciation: \-mət-ə\

: an abnormal excess accumulation of serous fluid in connective tissue or in a serous cavity —called also dropsy

Esophagitis

esoph*a*gi*tis
Function: noun
: inflammation of the esophagus

Fe

Fe
Function: symbol
iron

Flare-up

flare–up
Pronunciation: \-ˌəp\

Function: noun
: a sudden increase in the symptoms of a latent or subsiding disease <a flare-up of malaria>

Flatulence

flat*u*lence
Pronunciation: \ˈflach-ə-lən(t)s\


Function: noun
: the quality or state of being flatulent

Gastrectomy

gas*trec*to*my
Pronunciation: \ga-ˈstrek-tə-mē\


Function: noun
pl -mies
: surgical removal of all or part of the stomach

Gastritis

gas*tri*tis
Pronunciation: \ga-ˈstrīt-əs\


Function: noun
: inflammation esp. of the mucous membrane of the stomach

Gastroenteritis

gas*tro*en*ter*i*tis
Pronunciation: \-ˌent-ə-ˈrīt-əs\


Function: noun
pl -en*ter*it*i*des
Pronunciation: \-ˈrit-ə-ˌdēz\
: inflammation of the lining membrane of the stomach and the intestines

Gliadin

gli*a*din
Pronunciation: \ˈglī-əd-ən\


Function: noun
: see: prolamin; esp: one obtained by alcoholic extraction of gluten from wheat and rye

Glucagon

glu*ca*gon
Pronunciation: \ˈglü-kə-ˌgän\


Function: noun
: a protein hormone that is produced esp. by the pancreatic islets of Langerhans and that promotes an increase in the sugar content of the blood by increasing the rate of breakdown of glycogen in the liver —called also hyperglycemic factor, hyperglycemic-glycogenolytic factor

Gluten

glu*ten
Pronunciation: \ˈglüt-ən\


Function: noun
: a gluey protein substance esp. of wheat flour that causes dough to be sticky

Hemorrhoid

hem*or*rhoid
Function: noun
: a mass of dilated veins in swollen tissue at the margin of the anus or nearby within the rectum usu. used in pl.—called also piles

Hepatitis A

hepatitis A
Pronunciation: \-ˈā\


Function: noun
: an acute usu. benign hepatitis caused by a single-stranded RNA virus of the family Picornaviridae (species Hepatitis A virus of the genus Hepatovirus) that does not persist in the blood serum and is transmitted esp. in food and water contaminated with infected fecal matter —called also infectious hepatitis, see havrix

Hepatitis B

hepatitis B
Pronunciation: \-ˈbē\


Function: noun
: a sometimes fatal hepatitis caused by a double-stranded DNA virus (species Hepatitis B virus of the genus Orthohepadnavirus, family Hepadnaviridae) that tends to persist in the blood serum and is transmitted esp. by contact with infected blood (as by transfusion or by sharing contaminated needles in illicit intravenous drug use) or by contact with other infected bodily fluids (as semen) —called also serum hepatitis

Hepatitis C

hepatitis C
Pronunciation: \-ˈsē\


Function: noun
: hepatitis caused by a single-stranded RNA virus of the family Flaviviridae (species Hepatitis C virus of the genus Hepacivirus) that tends to persist in the blood serum and is usu. transmitted by infected blood (as by injection of an illicit drug, blood transfusion, or exposure to blood or blood products) and that accounts for most cases of non-A, non-B hepatitis

Hepatitis D

hepatitis D
Pronunciation: \-ˈdē\


Function: noun
: hepatitis that is similar to hepatitis B and is caused by coinfection with the hepatitis B virus and hepatitis D virus —called also delta hepatitis

Hepatitis E

hepatitis E
Pronunciation: \-ˈē\


Function: noun
: a hepatitis that is rare in the U.S. but is common in some third-world countries, is usu. contracted from sewage-contaminated water, and is caused by a highly variable single-stranded RNA virus (species Hepatitis E virus) of uncertain taxonomic affinities but related to members of the family Caliciviridae

Hepatocyte

he*pa*to*cyte
Pronunciation: \hi-ˈpat-ə-ˌsīt, ˈhep-ət-ə-\


Function: noun
: any of the polygonal epithelial parenchymatous cells of the liver that secrete bile —called also hepatic cell, liver cell

Hydrochloric Acid

hy*dro*chlo*ric acid
Pronunciation: \ˌhī-drə-ˌklōr-ik-, -ˌklor-\


Function: noun
: an aqueous solution of hydrogen chloride HCl that is a strong corrosive irritating acid, is normally present in dilute form in gastric juice, and is widely used in industry and in the laboratory —called also muriatic acid

Hyperalgesia

hy*per*al*ge*sia
Pronunciation: \ˌhī-pə-ral-ˈjē-zhə, -z(h)ē-ə\


Function: noun
: increased sensitivity to pain or enhanced intensity of pain sensation

Immune System

immune system
Function: noun
: the bodily system that protects the body from foreign substances, cells, and tissues by producing the immune response and that includes esp. the thymus, spleen, lymph nodes, special deposits of lymphoid tissue (as in the gastrointestinal tract and bone marrow), lymphocytes including the B cells and T cells, and antibodies

Interferon

in*ter*fer*on
Pronunciation: \ˌint-ə(r)-ˈfi(ə)r-ˌän\


Function: noun
: any of a group of heat-stable soluble basic antiviral glycoproteins of low molecular weight that are produced usu. by cells exposed to the action of a virus, sometimes to the action of another intracellular parasite (as a bacterium), or experimentally to the action of some chemicals, and that include some used medically as antiviral or antineoplastic agents see alpha interferon beta interferon gamma interferon

Interferon Alpha

interferon alpha
Function: noun
: see: alpha interferon

Lactase

lac*tase
Pronunciation: \ˈlak-ˌtās, -ˌtāz\


Function: noun
: an enzyme that hydrolyzes esp. lactose to glucose and galactose and occurs esp. in the intestines of young mammals and in yeasts

Laparoscopy

lap*a*ros*co*py
Pronunciation: \ˌlap-ə-ˈräs-kə-pē\


Function: noun
pl -pies

1: visual examination of the inside of the abdomen by means of a laparoscope —called also peritoneoscopy
2: an operation (as tubal ligation or gallbladder removal) involving laparoscopy

Laxative

1lax*a*tive
Pronunciation: \ˈlak-sət-iv\


Function: adjective

1: having a tendency to loosen or relax; specif: relieving constipation
2: see: lax 2

Lumen

lu*men
Pronunciation: \ˈlü-mən\


Function: noun
pl lu*mi*na
Pronunciation: \-mə-nə\
or lumens

1: the cavity of a tubular organ <the lumen of a blood vessel>
2: the bore of a tube (as of a hollow needle or catheter)
3: a unit of luminous flux equal to the light emitted in a steradian by a uniform point source of one candle intensity

Magnesium

mag*ne*sium
Pronunciation: \mag-ˈnē-zē-əm, -zhəm\


Function: noun
: a silver-white light malleable ductile metallic element that occurs abundantly in nature (as in bones and seeds and in the form of chlorophyll in the green parts of plants) and is used in metallurgical and chemical processes, in photography, in signaling, and in the manufacture of pyrotechnics because of the intense white light it produces on burning, and in construction esp. in the form of light alloys symbol Mgsee element table

Malabsorption

mal*ab*sorp*tion
Pronunciation: \ˌmal-əb-ˈsorp-shən, -ˈzorp-\


Function: noun
: faulty absorption of nutrient materials from the alimentary canal —called also malassimilation

Motility

mo*til*i*ty
Pronunciation: \mō-ˈtil-ət-ē\


Function: noun
pl -ties
: the quality or state of being motile : see: contractility<gastrointestinal motility>

Nontropical Sprue

non*trop*i*cal sprue
Pronunciation: \-ˈträp-i-kəl-\


Function: noun
: see: celiac disease

Pancreatitis

pan*cre*ati*tis
Pronunciation: \ˌpaŋ-krē-ə-ˈtīt-əs, ˌpan-\



Function: noun
1: inflammation of the pancreas

Parenteral

1par*en*ter*al
Pronunciation: \pə-ˈrent-ə-rəl\


Function: adjective
: situated or occurring outside the intestine <parenteral[1] drug administration by intravenous, intramuscular, or subcutaneous injection> ; esp: introduced otherwise than by way of the intestines <enteric versus parenteral[1] feeding>

Peptic Ulcer

peptic ulcer
Function: noun
: an ulcer in the wall of the stomach or duodenum resulting from the digestive action of the gastric juice on the mucous membrane when the latter is rendered susceptible to its action (as from infection with the bacterium Helicobacter pylori or the chronic use of NSAIDs)

Peristalsis

peri*stal*sis
Pronunciation: \ˌper-ə-ˈstol-səs, -ˈstäl-, -ˈstal-\


Function: noun
pl -stal*ses
Pronunciation: \-ˌsēz\
: successive waves of involuntary contraction passing along the walls of a hollow muscular structure (as the esophagus or intestine) and forcing the contents onward compare segmentation 2

Peritonitis

peri*to*ni*tis
Pronunciation: \ˌper-ət-ən-ˈīt-əs\


Function: noun
: inflammation of the peritoneum

Radiation Therapy

radiation therapy
Function: noun
: see: radiotherapy

Reflux

1re*flux
Pronunciation: \ˈrē-ˌfləks\


Function: noun

1 a: a flowing back : see: regurgitation<reflux[1] of gastric acid> <mitral valve reflux[1]>
b: see: gastroesophageal reflux
2: a process of refluxing or condition of being refluxed <the sample was hydrolyzed…under reflux[1] for 24 hours T. Y. Ho et al>

Remission

re*mis*sion
Pronunciation: \ri-ˈmish-ən\


Function: noun
: a state or period during which the symptoms of a disease are abated <cancer in remission after treatment> compare arrest cure 1 intermission

Resection

re*sec*tion
Pronunciation: \ri-ˈsek-shən\


Function: noun
: the surgical removal of part of an organ or structure <pancreatic resection> <resection of the lower bowel> <resection of a tumor> see abdominoperineal resection mikulicz resection segmental resection wedge resection

Rotavirus

ro*ta*vi*rus
Pronunciation: \ˈrōt-ə-ˌvī-rəs\


Function: noun
: any of a genus (Rotavirus) of double-stranded RNA viruses of the family Reoviridae that have a capsid composed of two layers and cause diarrhea esp. in young vertebrates including human infants and young children

Sigmoidoscopy

sig*moid*os*co*py
Pronunciation: \ˌsig-ˌmoi-ˈdäs-kə-pē\


Function: noun
pl -pies
: the process of using a sigmoidoscope —called also proctosigmoidoscopy

Small Bowel

small bowel
Pronunciation: \ˈsmol-\


Function: noun
: see: small intestine

Steroid

ste*roid
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

Stool

stool
Pronunciation: \ˈstül\


Function: noun
: a discharge of fecal matter

Stricture

stric*ture
Pronunciation: \ˈstrik-chər\


Function: noun
: an abnormal narrowing of a bodily passage (as from inflammation, cancer, or the formation of scar tissue) <esophageal stricture> ; also: the narrowed part

Tenesmus

te*nes*mus
Pronunciation: \tə-ˈnez-məs\


Function: noun
: a distressing but ineffectual urge to evacuate the rectum or urinary bladder

Ulcer

2ulcer
Function: verb
ul*cered
ul*cer*ing
Pronunciation: \ˈəls-(ə-)riŋ\


: see: ulcerate

Vaccine

vac*cine
Pronunciation: \vak-ˈsēn, ˈvak-ˌ\


Function: noun

1: matter or a preparation containing the virus of cowpox used to vaccinate a person against smallpox
2: a preparation of killed microorganisms, living attenuated organisms, or living fully virulent organisms that is administered to produce or artificially increase immunity to a particular disease <chicken pox vaccine> ; also: a mixture of several such vaccines <measles-mumps-rubella vaccine>

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