islet
n.a small island, or a small group of cells in the body that do a specific job. In biology, it often refers to the tiny clusters of cells in the pancreas that make insulin.
n.a small island or a small cluster of cells within a larger organ. In a biological context, it specifically refers to the islets of Langerhans in the pancreas, which regulate blood sugar levels.
“The doctor checked the islet cells in the patient's pancreas.”
“Researchers are studying how to protect the islet cells from the immune system to treat diabetes more effectively.”
From Middle French islette. By surface analysis, is(le) + -let. Mostly displaced native Middle English eyt, eit and Middle English holm, holme (See eyot and holm for more).
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.