du·​o·​de·​num | \ ˌdü-ə-ˈdē-nəm How to pronounce duodenum (audio) , du̇-ˈä-də-nəm How to pronounce duodenum (audio) also (ˌ)dyü- \
plural duodena\ ˌdü-​ə-​ˈdē-​nə How to pronounce duodena (audio) , du̇-​ˈä-​də-​nə \ or duodenums

Definition of duodenum

: the first part of the small intestine extending from the pylorus to the jejunum

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Other Words from duodenum

duodenal \ ˌdü-​ə-​ˈdē-​nᵊl How to pronounce duodenal (audio) , du̇-​ˈä-​də-​nəl How to pronounce duodenal (audio) \ adjective

Examples of duodenum in a Sentence

Recent Examples on the Web The tube is inserted through the patient’s mouth and stomach, then into the first part of the small intestine, called the duodenum. Roni Caryn Rabin, New York Times, "These Medical Devices Are Inserted Into 500,000 Patients Each Year — but Are Tough to Sterilize," 6 Aug. 2019 Duke University researchers have observed rudimentary, but functional, stomachs, small intestines, and duodenums growing inside cancerous lungs — illustrating how varied and plastic these metastatic cells can be. Meghana Keshavan, STAT, "Scientists find mini gastrointestinal tract growing inside tumor," 29 Mar. 2018 He was hospitalized, but physicians were unaware of a perforated duodenum, a portion of the small intestine, the complaint says. Megan Cassidy, azcentral, "After recent $7 million settlement, a look at 5 other payouts from Arpaio-era jail deaths," 9 Mar. 2018 The researchers speculate that bacteria may invade pancreatic tumors by migrating from the duodenum, the top section of the small intestine. Beth Mole, Ars Technica, "See jerkface bacteria hiding in tumors and gobbling chemotherapy drugs," 17 Sep. 2017

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

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First Known Use of duodenum

14th century, in the meaning defined above

History and Etymology for duodenum

Middle English, from Medieval Latin, from Latin duodeni twelve each, from duodecim twelve; from its length, about 12 fingers' breadth

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Time Traveler for duodenum

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The first known use of duodenum was in the 14th century

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Cite this Entry

“Duodenum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/duodenum. Accessed 29 Oct. 2020.

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More Definitions for duodenum


How to pronounce duodenum (audio) How to pronounce duodenum (audio)

English Language Learners Definition of duodenum

medical : the part of the small intestine that is right below your stomach


du·​o·​de·​num | \ ˌd(y)ü-ə-ˈdē-nəm How to pronounce duodenum (audio) , d(y)u̇-ˈäd-ᵊn-əm How to pronounce duodenum (audio) \
plural duodena\ -​ˈdē-​nə, -​ᵊn-​ə How to pronounce duodena (audio) \ or duodenums

Medical Definition of duodenum

: the first, shortest, and widest part of the small intestine that in humans is about 10 inches (25 centimeters) long and that extends from the pylorus to the undersurface of the liver where it descends for a variable distance and receives the bile and pancreatic ducts and then bends to the left and finally upward to join the jejunum near the second lumbar vertebra

Other Words from duodenum

duodenal \ -​ˈdēn-​ᵊl How to pronounce duodenal (audio) , -​ᵊn-​əl How to pronounce duodenal (audio) \ adjective

More from Merriam-Webster on duodenum

Britannica.com: Encyclopedia article about duodenum

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