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ileum Line breaks: ileum
Pronunciation: /ˈɪlɪəm/

Definition of ileum in English:

noun (plural ilea /ɪlɪə/)

The third portion of the small intestine, between the jejunum and the caecum.
Example sentences
  • The midgut eventually develops into distal duodenum, jejunum, ileum, caecum, appendix, ascending colon, and proximal two thirds of the transverse colon.
  • The latter might be a confusion with ileum, the third portion of the small intestine.
  • Ultimately, the shunts were converted to jejunoileostomies in which the upper portion of the jejunum was anastomosed to the lower portion of the ileum.


Example sentences
  • Two tumors were spindle cell leiomyosarcomas (gastric and ileac); 1 was an epithelioid leiomyosarcoma of the colon; and 1 was an epithelioid GIST of the colon.
Pronunciation: /ˈɪlɪəl/
Example sentences
  • Sections from the ileum showed the polyps to be composed of multiple closely aggregated lymphoid follicles in the lamina propria of the ileal mucosa.
  • Hydrochloric acid and pepsin secreted by the gastric mucosa cause the adjacent ileal mucosa of the intestine to erode and ulcerate since the normal protective mucosa is missing.
  • Their mesentery contains ileal arteries and veins, which are also branches of the superior mesenteric artery.


Late 17th century: from medieval Latin, variant of ilium.

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