insulin

noun

in·​su·​lin ˈin(t)-s(ə-)lən 

: 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

Structure is also developing an oral drugs that targets amylin, an emerging form of weight loss treatment that mimics a hormone co-secreted with insulin in the pancreas to suppress appetite and reduce food intake. —Annika Kim Constantino, CNBC, 23 Jan. 2026

Some components of dragon’s blood appear to help regulate blood sugar levels by improving insulin sensitivity and glucose metabolism. —Scott Travers, Forbes.com, 21 Jan. 2026

Trump’s immigration crackdown is keeping Minnesota patients from seeking medical care, with pregnant women avoiding prenatal visits and diabetics afraid to pick up insulin. —Tim Sullivan, Los Angeles Times, 21 Jan. 2026

The sugar enters your bloodstream, prompting the pancreas to produce insulin, a hormone that moves sugar out of the blood and into the cells for energy. —Kirsten Nunez, Martha Stewart, 21 Jan. 2026

Word History

Etymology

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

First Known Use

1914, in the meaning defined above

Phrases Containing insulin

• insulin-dependent diabetes
• insulin-dependent diabetes mellitus
• insulin-like growth factor
• insulin resistance
• insulin resistance syndrome
• insulin shock
• non-insulin-dependent diabetes
• non-insulin-dependent diabetes mellitus

Kids Definition

insulin

noun

in·​su·​lin ˈin(t)-s(ə-)lən 

: 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 

: 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