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

Throughout the trial, the scientists monitored a wide variety of physiological factors, including the animals' weight, glucose tolerance, insulin sensitivity, hormone levels, internal inflammation and the specific composition of their gut bacteria. —Khloe Quill, FOXNews.com, 18 June 2026

Animal studies suggest that these compounds have antidiabetic, antioxidant, lipid-lowering, and anti-inflammatory qualities that can improve fasting glucose and insulin sensitivity. —Anna Giorgi, Verywell Health, 17 June 2026

Their heart rates stayed elevated through the night in a kind of superficial pseudo-sleep, and their insulin function was that of a prediabetic. —Literary Hub, 17 June 2026

This creates a gradual increase in blood sugar, which lessens the amount of insulin your body needs to help regulate it. —Kirsten Nunez, Martha Stewart, 15 June 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