in·​su·​lin | \ ˈin(t)-s(ə-)lən How to pronounce insulin (audio) \

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 Type 1 diabetes is a condition where your pancreas (a large gland that sits behind your stomach) doesn’t make much or any insulin. Korin Miller,, "What Causes Type 1 Diabetes? 3 Things You Need to Know, According to Doctors," 22 Nov. 2019 The company has faced repeated criticism, however, for the high price of its insulin and other life-saving medicines for those with diabetes. Shari Rudavsky, Indianapolis Star, "Lilly to announce $400M investment in Indianapolis manufacturing along with new jobs," 20 Nov. 2019 And in type 1 diabetes, the body does not make insulin or makes very little. Sarah Jacoby, SELF, "10 Signs and Symptoms of High Blood Sugar to Be Aware Of," 6 Nov. 2019 But pinpointing where the insulin came from will be challenging. Dennis Wagner, USA TODAY, "Oversights, lapses at VA hospital risked veterans’ lives, limit evidence in homicide probe," 30 Aug. 2019 Similarly, better insulin sensitivity and beta cell function were associated with the highest serum 25(OH)D quartile (≥34.9 ng/mL). Mackie Shilstone,, "Vitamin D reduces risk to fat gain in old age," 19 June 2019 Among other effects, contracting muscles burn blood sugar as fuel and, in response to signals from the hormone insulin, also store some for future use. Gretchen Reynolds, The Seattle Times, "Planning a break from exercise? Think twice," 8 Aug. 2018 Last June, she was approved for the Novo Nordisk assistance program, allowing her to begin taking the Novolog insulin again. New York Times, "The Price They Pay," 5 Mar. 2018 Since the deaths last year, the Clarksburg VA has tightened the control of insulin on hospital wards. Donovan Slack, USA TODAY, "'National tragedy': Surveillance, staffing under review after deaths at VA hospital," 16 Nov. 2019

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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Time Traveler for insulin

Time Traveler

The first known use of insulin was in 1914

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Statistics for insulin

Last Updated

5 Dec 2019

Cite this Entry

“Insulin.” The Dictionary, Merriam-Webster Inc., Accessed 14 December 2019.

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More Definitions for insulin


How to pronounce insulin (audio)

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 How to pronounce insulin (audio) \

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 How to pronounce insulin (audio) \

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

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