Insulin

Part of speech: noun

Pronunciation: /ˈɪnsjʊlin/

Definitions

1. A hormone produced by the pancreas which is essential for managing blood sugar levels while also influencing fat and carbohydrate metabolism
2. A hormone made by the pancreas that helps control blood sugar levels and also affects how the body metabolizes fats and carbohydrates
3. A hormone secreted by the pancreas that regulates the amount of glucose in the bloodstream

Etymology: The name "insulin" points to a small cluster of cells in the pancreas. In the 1860s, the German medical student Paul Langerhans described tiny clumps of cells scattered through the gland, and they came to be called the islets of Langerhans, from Latin "insula" meaning "island." The hormone was later found to be made in these islets, so the substance took its name from them, with the suffix "-in" added in the usual way for chemical substances. The word is therefore a case of a place-name-style label outliving the anatomy it first described. The islets look like scattered islands of tissue against the surrounding gland, and the name was given to the structure before anyone knew what those cells did. When the hormone was isolated, the naming logic carried over, so a term for cell clusters became the name of a molecule.