Anatomy A large, reddish-brown, glandular vertebrate organ located in the upper right portion of the abdominal cavity that secretes bile and is active in the formation of certain blood proteins and in the metabolism of carbohydrates, fats, and proteins. An organ in invertebrates that is similar to the vertebrate liver. The bile-secreting organ of an animal, used as food. A dark reddish brown. Made of or flavored with liver: liver p\u00e2t\u00e9; liver sandwiches. Of a dark reddish brown. One who lives in a specified manner: a high liver.