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

The way your body uses insulin can seem complicated. —Julia Ries, Health, 9 Apr. 2025

People with diabetes who are using insulin, taking medication that lowers blood glucose, or are at risk of ketoacidosis should proceed with caution and be supervised by a healthcare professional. —Melissa Nieves, Verywell Health, 9 Apr. 2025

These include no cost sharing for vaccines, a $35 insulin cap and the $2,000 cap on out-of-pocket costs for covered medications. —Diane Omdahl, Forbes.com, 2 Apr. 2025

Bombarded by fatty trespassers and inflammation, your organ tissues may struggle to recognize and respond to insulin, the hormone that prompts them to metabolize sugar. —Erica Sloan, SELF, 26 Mar. 2025

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