in·su·lin | \ˈin(t)-s(ə-)lən \

Definition of insulin 

: a protein pancreatic hormone secreted by the beta cells of the islets of Langerhans that is essential especially for the metabolism of carbohydrates and the regulation of glucose levels in the blood and that when insufficiently produced results in diabetes mellitus

Examples of insulin in a Sentence

Recent Examples on the Web

Al-Aly explained that these small, noxious particles enter the body and reduce its ability to respond to insulin. Hannah Holzer, sacbee, "Air pollution increases risk for type 2 diabetes, study finds," 12 July 2018 The veterinarians suspected that the animal’s newfound resistance to insulin might have been caused by Cushing’s disease, an endocrine problem triggered by too much of the stress hormone cortisol. Karen Weintraub, New York Times, "Doctor, Your Patient Is Waiting. It’s a Red Panda.," 29 June 2018 And in Type 2, the most common category of diabetes accounting for 90-95 percent of all cases, the body’s cells either stop responding to insulin or the beta cells can’t produce enough of the hormone. Fiza Pirani, ajc, "Common vaccine may reverse advanced diabetes cases, study finds," 21 June 2018 The price of insulin and other supplies required to manage diabetes are climbing in the U.S. and doctors and patients are struggling to find solutions. Aubrey Nagle,, "Protesters rally in Rittenhouse Square, Senior Week puts the 'wild' in Wildwood | Morning Newsletter," 20 June 2018 Type 1 diabetes causes the pancreas to produce little or no insulin and impacts about 1.25 million Americans. Rubi Jones, Teen Vogue, "The Haim Sisters Open Up About Their Firsthand Experiences With Harassment and Unequal Pay," 16 June 2018 Clinic workers set out in trucks, on foot and on horseback, delivering critical supplies like the pain medicine and insulin Rivera needs. Jenny Vrentas,, "Five Giants, and Those Forgotten After the Storm," 23 May 2018 With the help of old-school genetic engineering techniques, scientists have already reprogrammed microbes like E. Coli and brewer’s yeast into factories that can make everything from insulin to ethanol. Megan Molteni, WIRED, "The WIRED Guide to Crispr," 27 Apr. 2018 So protein also stimulates insulin, but not as much. Sandy Bauers,, "Good fats, bad fats, and why the ketogenic diet matters," 13 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'insulin.' 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 insulin

1914, in the meaning defined above

History and Etymology for insulin

New Latin insula islet (of Langerhans), from Latin, island

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Last Updated

10 Oct 2018

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The first known use of insulin was in 1914

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English Language Learners Definition of insulin

medical : a substance that your body makes and uses to turn sugar into energy


in·su·lin | \ˈin-sə-lən \

Kids Definition of insulin

: a hormone made by the pancreas that helps the cells in the body take up glucose from the blood and that is used to treat diabetes


in·su·lin | \ˈin(t)-s(ə-)lən \

Medical Definition of insulin 

: a protein hormone that is synthesized in the pancreas from proinsulin and secreted by the beta cells of the islets of Langerhans, that is essential for the metabolism of carbohydrates, lipids, and proteins, that regulates blood sugar levels by facilitating the uptake of glucose into tissues, by promoting its conversion into glycogen, fatty acids, and triglycerides, and by reducing the release of glucose from the liver, and that when produced in insufficient quantities results in diabetes mellitus — see iletin

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More from Merriam-Webster on insulin

Spanish Central: Translation of insulin

Nglish: Translation of insulin for Spanish Speakers

Britannica English: Translation of insulin for Arabic Speakers Encyclopedia article about insulin

Comments on insulin

What made you want to look up insulin? Please tell us where you read or heard it (including the quote, if possible).


exaggeratedly or childishly emotional

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