il·​e·​um | \ ˈi-lē-əm How to pronounce ileum (audio) \
plural ilea\ ˈi-​lē-​ə How to pronounce ilea (audio) \

Definition of ileum

: the last division of the small intestine extending between the jejunum and large intestine

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Other Words from ileum

ileal \ ˈi-​lē-​əl How to pronounce ileal (audio) \ adjective

Examples of ileum in a Sentence

Recent Examples on the Web View Sample Sign Up Now Instead, the sugar and other components of fruit quickly move farther down the small intestine to the jejunum and ileum. Markham Heid, Time, "Is It Possible To Eat Too Much Fruit?," 6 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ileum.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of ileum

1682, in the meaning defined above

History and Etymology for ileum

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

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Time Traveler for ileum

Time Traveler

The first known use of ileum was in 1682

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Statistics for ileum

Cite this Entry

“Ileum.” Dictionary, Merriam-Webster, Accessed 23 Sep. 2020.

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More Definitions for ileum


il·​e·​um | \ ˈil-ē-əm How to pronounce ileum (audio) \
plural ilea\ -​ē-​ə How to pronounce ilea (audio) \

Medical Definition of ileum

: 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

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