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Related to intestine: large intestine


the part of the alimentary canal extending from the pyloric opening of the stomach to the anus. It is a membranous tube, comprising the small intestine and large intestine; called also bowel and gut. See also intestinal tract, and see color plates.


(in-tes'tin), [TA]
The digestive tube passing from the stomach to the anus. It is divided primarily into the small intestine (intestinum tenue) and the large intestine (intestinum crassum).
Synonym(s): bowel, gut (1) , intestinum (1)
[L. intestinum]


n. often intestines
The portion of the digestive tract extending from the stomach to the anus and, in humans and other mammals, consisting of two segments, the small intestine and the large intestine.
Internal; civil: the intestine affairs of the nation.


(in-tes'tin) [TA]
1. The digestive tube passing from the stomach to the anus. It is divided primarily into the intestinum tenue (small intestine) and the intestinum crassum (large intestine).
2. Inward; inner.
Synonym(s): intestinum [TA] , bowel, gut (1) .
[L. intestinum ]


(in-tes'tin) [L. intestinum]
The portion of the alimentary canal that extends from the pylorus of the stomach to the anus. It includes the duodenum, jejunum, ileum (small intestine), and colon (large intestine) and is responsible for the completion of digestion and the absorption of nutrients and water. Synonym: bowel; gut (1) See: abdomen
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SMALL INTESTINE: (duodenum, jejunum, ileum)
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large intestine

The large intestine extends from the ileum to the anus and is about 1.5 m (5 ft) in length. It absorbs water, minerals, and vitamins from the intestinal contents and eliminates undigested material during defecation. The mucosa has no villi but contains glands that secrete mucus. Hyperactivity of the colon may cause diarrhea. See: illustration

The first part of the large intestine is the cecum, a pouch on the right side into which the ileum empties. Attached to the cecum is the vermiform appendix, about 7.5 to 10.4 cm (3 to 4 in) long. The ascending colon extends from the cecum upward to the undersurface of the liver, where it turns left (hepatic flexure) and becomes the transverse colon, which continues toward the spleen and turns downward (splenic flexure) to become the descending colon. At the level of the pelvic brim, the descending colon turns inward in the shape of the letter S and is then called the sigmoid colon. The rectum, about 10.2 to 12.7 cm (4 to 5 in) long, is the straight part that continues downward; the last 2.5 cm (1 in) is called the anal canal, which surrounds the anus.


small intestine

The first part of the small intestine is the duodenum, approx. 8 to 11 in (20 to 28 cm) long, which receives chyme from the stomach through the pyloric orifice and, by way of the common bile duct, bile from the liver and gallbladder, and pancreatic juice from the pancreas. The second part is the jejunum, about 9 ft (2.8 m) long. The third part is the ileum, about 13 ft (4 m) long. The ileum opens into the cecum of the large intestine, and the ileocecal valve prevents backup of intestinal contents.

The wall of the small intestine has circular folds (plicae circulares), which are folds of the mucosa and submucosa that look like accordion pleats. The mucosa is further folded into villi, which look like small (0.5 to 1.5 mm long) projections. The free surfaces of the epithelial cells have microscopic folds called microvilli that are collectively called the brush border. All of the folds increase the surface area for absorption of the end products of digestion. Intestinal glands (of Lieberkühn) between the bases of the villi secrete enzymes. The duodenum has submucosal Brunner's glands that secrete mucus. Enzymes secreted by the small intestine are peptidases, which complete protein digestion, and sucrase, maltase, and lactase, which digest disaccharides to monosaccharides. Some of these enzymes function in the brush border rather than in the lumen of the intestine. Hormones secreted by the duodenum are gastric inhibitory peptide, secretin, and cholecystokinin; these influence secretions or motility of other parts of the digestive tract.

The end products of digestion (amino acids, monosaccharides, fatty acids, glycerol, vitamins, minerals, and water) are absorbed into the capillaries or lacteals within the villi. Blood from the small intestine passes through the liver by way of the portal vein before returning to the heart.

See: duodenum; liver; pancreas


The part of the digestive system lying between the outlet of the stomach (the PYLORUS) and the ANUS. It consists, sequentially, of the DUODENUM, the JEJUNUM, the ILEUM, the wide, pouch-like caecum, that carries the APPENDIX, the large intestine, or COLON, the S-shaped SIGMOID colon, the RECTUM and anus.


the part of the alimentary canal that lies between the stomach and the anus. Usually it is coiled and the internal surface is greatly increased by the presence of folds and projections (VILLI) to allow efficient digestion and absorption. Anteriorly, the intestine is lined with an EPITHELIUM containing ENZYME and MUCUS-secreting glands, and in higher vertebrates it is referred to as the SMALL INTESTINE. The posterior, large intestine, dehydrates the faeces which are stored here until voided in DEFECATION.


Also called the bowels and divided into large and small intestine, they extend from the stomach to the anus, where waste products exit the body. The small intestine is about 20 ft (6.1m) long and the large intestine, about 5 ft (1.5m) long.
Mentioned in: Colostomy, Enemas

Patient discussion about intestine

Q. I recently had my surgery for bowel obstruction? I recently had my surgery for bowel obstruction? None of the diet was restricted for me by doctor but should I go for any special diet.

A. I had surgery in 08/08 during having a c-section and hernia repair, and I'm having diarrhea all the time. I don't know what to eat nor what medicines to take. Only Immodium AD helps temporary. If I have an appointment, I don't eat breakfast or lunch. I come home and eat dinner. About 30 minutes after eating, I'm in the bathroom. Can someone help me please? I have to return back to work next month, and I don't want to be in the bathroom more than I am at my desk.

Q. Can Alcoholism makes you vulnerable to intestine infections? A friend of mine is a heavy drinker, he had something like 5 infections in the past year. Is it connected?

A. yes

Q. What is the connection between bowel disease and arthritis? My son suffers from ulcerative colitis, and the doctor said that his recent joint pain can be as a result of the colitis. Why is that?

A. Although ulcerative colitis happens mainly in the colon, it is a systemic disease, and patients may present with symptoms and complications outside the colon. These include musculoskeletal complications such as arthritis (for instance- ankylosing spondylitis). The exact mechanism of this injury is unknown.

More discussions about intestine
References in periodicals archive ?
If there is an inflammatory reaction, two changes occur: first, more monocytes or macrophages are recruited into the small intestine and second, there is a dramatic change in their gene expression.
This, along with a more continuous movement of bile into the small intestines, can have a laxative effect, leading to diarrhea.
In the most severe cases of short bowel syndrome, small intestine transplant from donor tissue is the only answer; but this, too, comes with its own list of problems.
Hedgehog, Small intestine, Microstructure, Mast cells.
The team found that once in the intestine of rats, LuCI can coat the gut, forming a thin barrier that alters nutrient contact and lowers blood glucose response after a meal.
The project will see computers break down the size, shape and structure of images of the intestine's cells into a matrix of numbers.
A large segment of the intestine can become critically ischemic with infarction and loss of intestine.
The surgeons found a section of her small intestines had herniated through a defect of the rectus sheath, which they said was not in any way linked to the C-section.
The team then selected cells from these organoids and placed them inside the Intestine-Chips, which are about the size of AA batteries and re-create the natural microenvironment of the human intestine, including the intestinal epithelium--the layer of cells that forms the lining of both the small and large intestines.
After the cancerous portions of his large intestine are removed, it would then be reconnected.
The small intestine, with particularly villi and crypts, which increase absorbing surface area, has an extremely important role in the final stage of nutrients digestion and assimilation (Wang and Peng, 2008).
Called the mesentery, it was previously overlooked as part of the intestines.