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

Type 2 Diabetes Type 2 diabetes develops when the body becomes resistant to insulin or doesn't produce enough to regulate glucose (blood sugar) levels. —Lindsay Curtis, Health, 4 Sep. 2025

Metabolic biomarkers are also predictive of longevity and test blood glucose levels and insulin sensitivity. —Alexa Mikhail, Flow Space, 4 Sep. 2025

Adequate magnesium levels may help improve insulin sensitivity and glucose uptake, potentially reducing the risk of type 2 diabetes in women with PCOS. —Team Verywell Health, Verywell Health, 4 Sep. 2025

If such adjustments are not made, insulin is resisted, and glucose cannot enter. —Bryant Stamford, Louisville Courier Journal, 4 Sep. 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