A "beef brain" is the edible brain of a cow, considered an offal cut of meat, rich in nutrients like choline and omega-3 fatty acids, but also high in cholesterol, often used in various cuisines, though consumption can be limited due to concerns about potential diseases like bovine spongiform encephalopathy ("mad cow disease") linked to nervous tissue in cattle; it requires careful preparation due to its delicate texture and needs thorough cleaning before cooking.