insulin: Meaning and Definition of

in•su•lin

1. a polypeptide hormone, produced by the beta cells of the islets of Langerhans of the pancreas, that regulates the metabolism of glucose and other nutrients.
2. any of several commercial preparations of this substance, each of which allows a particular rate of absorption into the system: genetically engineered or obtained from the pig or ox pancreas, and used in the treatment of diabetes to restore the normal ability of the body to utilize sugars and other carbohydrates.