insulin

noun

in·​su·​lin ˈin(t)-s(ə-)lən How to pronounce insulin (audio)
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Several different types of peptides are naturally found in the body, like insulin and endorphins. — Renée Onque, CNBC, 24 Oct. 2026 Gut microbiome and insulin sensitivity may be affected in some people. — Brittany Poulson, Verywell Health, 23 Oct. 2026 Berries Berries, such as blueberries, raspberries, and blackberries, may help regulate blood sugar levels and lower post-meal insulin spikes. — Jillian Kubala, HEALTH, 23 Oct. 2026 Including cottage cheese in meals may also support blood glucose management by prompting a greater insulin response than some other proteins, according to a few small studies on both healthy participants and people with type 2 diabetes. — Kristen Rogers, CNN Money, 22 Oct. 2026 See All Example Sentences for insulin

Word History

Etymology

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

First Known Use

1914, in the meaning defined above

Time Traveler
The first known use of insulin was in 1914

Phrases Containing insulin

Browse Nearby Words

insulator
insulin
insulin-dependent diabetes
See all Nearby Words

Cite this Entry

“Insulin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/insulin. Accessed 27 Oct. 2026.

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Kids Definition

insulin

noun
in·​su·​lin ˈin(t)-s(ə-)lən How to pronounce insulin (audio)
: a hormone that is produced by the pancreas and is necessary for the normal use of glucose by the body

Medical Definition

insulin

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

More from Merriam-Webster on insulin

Britannica.com: Encyclopedia article about insulin

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