ileum

noun

il·​e·​um ˈi-lē-əm How to pronounce ileum (audio)
plural ilea ˈi-lē-ə How to pronounce ileum (audio)
: the last division of the small intestine extending between the jejunum and large intestine
ileal adjective

Examples of ileum in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Most absorption of vitamin B12 occurs in the ileum, the last and longest section of your small intestine. Anna Giorgi, Verywell Health, 6 Nov. 2024 Next, the second part of the small intestine, the jejunum, is surgically separated from the first section (the duodenum) and the last section (the ileum). Amber J. Tresca, Verywell Health, 5 July 2024 The duodenum and the ileum are connected together, bypassing the jejunum. Amber J. Tresca, Verywell Health, 5 July 2024 The diameters of the jejunum and ileum remained stable, maintaining a favorable jejunum-to-ileum ratio, and the strength of the anastomosis improved. The Salt Lake Tribune, 16 Aug. 2023 Sometimes, the ability of the terminal ileum (the part of the intestine where bile salts are reabsorbed) gets overwhelmed, and bile acids enter the colon, causing diarrhea. Dr. Keith Roach, oregonlive, 19 July 2023 The Roux-en-Y operation shortens the intestine, bringing food into the ileum much earlier in the digestive process. Bijal P Trivedi, Discover Magazine, 24 Oct. 2012 The final stretch of small intestine, the ileum, secretes incretins and absorbs more nutrients before emptying into the large intestine for elimination. Bijal P Trivedi, Discover Magazine, 24 Oct. 2012 Small bowel obstruction originating from thickened and enhancing terminal ileum. Tony Dajer, Discover Magazine, 19 Feb. 2011

Word History

Etymology

New Latin, alteration of Latin ilia, plural, groin, viscera

First Known Use

1682, in the meaning defined above

Time Traveler
The first known use of ileum was in 1682

Dictionary Entries Near ileum

Cite this Entry

“Ileum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ileum. Accessed 1 Dec. 2024.

Kids Definition

ileum

noun
il·​e·​um ˈil-ē-əm How to pronounce ileum (audio)
plural ilea -ē-ə How to pronounce ileum (audio)
: the last part of the small intestine between the jejunum and the large intestine
ileal adjective

Medical Definition

ileum

noun
il·​e·​um ˈil-ē-əm How to pronounce ileum (audio)
plural ilea -ē-ə How to pronounce ileum (audio)
: the last division of the small intestine that constitutes the part between the jejunum and large intestine and in humans forms the last three fifths of the part of the small intestine beyond the end of the duodenum and that is smaller and thinner-walled than the jejunum with fewer circular folds but more numerous Peyer's patches

More from Merriam-Webster on ileum

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