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

Only part of the sugar is absorbed in the small intestine, while much of it is fermented by gut bacteria in the colon.

From Science Daily • Jan. 13, 2026

Charles-Barclay said it took about a year for her small intestine to heal after making the necessary changes to her diet.

From BBC • Dec. 10, 2025

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

From BBC • Dec. 7, 2025

"I think we're going to uncover multiple new mechanisms for how these amino acids regulate cell fate decisions and gut health in the small intestine and colon," Yilmaz says.

From Science Daily • Oct. 23, 2025

The tumor in the small intestine is harder to measure.

From "All the Light We Cannot See" by Anthony Doerr