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
ˈi-lē-əl How to pronounce ileum (audio)
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.
This opening below the new stomach is then connected to a part of the lower small intestine called the ileum. — Lea Veloso, StyleCaster, 27 Mar. 2025 Urine flow is rerouted through the abdominal wall via the ileum to a stoma. — Jamin Brahmbhatt, Verywell Health, 12 Feb. 2025

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

Rhymes for ileum

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Browse Nearby Words

ilesite
ileum
ileus
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Cite this Entry

“Ileum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ileum. Accessed 7 Apr. 2025.

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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
-ē-əl How to pronounce ileum (audio)
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

Britannica.com: Encyclopedia article about ileum

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