small intestine

American  

noun

Anatomy.

1. intestine.

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small intestine British  

noun

1. the longest part of the alimentary canal, consisting of the duodenum, jejunum, and ileum, in which digestion is completed Compare large intestine

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small intestine Scientific  

1. The long, narrow, coiled section of the intestine that extends from the stomach to the beginning of the large intestine. Nutrients from food are absorbed into the bloodstream from the small intestine. In mammals, it is made up of the duodenum, jejunum, and ileum.

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small intestine Cultural  

1. The upper portion of the intestines, extending from the stomach to the large intestine, where the digestion of food takes place. The small intestine is about twenty feet long in adults.

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Etymology

Origin of small intestine

First recorded in 1760–70

Example Sentences

Duodenal mucosal resurfacing is an investigational endoscopic treatment that uses controlled heat to remove damaged tissue from the inner lining of the duodenum, the first section of the small intestine just below the stomach.

From Science Daily • Apr. 23, 2026

In humans, intelectin-2 is consistently produced by Paneth cells in the small intestine.

From Science Daily • Mar. 16, 2026

Explaining how it works, Ghosh said small electrodes placed on the abdomen detected the activity of the muscle of the small intestine.

From BBC • Mar. 11, 2026

But he was saved by three major surgeries in which most of his small intestine was removed.

From BBC • Dec. 7, 2025

After that a piece of his small intestine had to go.

From "The Milagro Beanfield War" by John Nichols