Liver
A liver was an organ.
In Mesopotamia, the livers of animals sacrificed to Ishtar were used for divination. (PROSE: Timewyrm: Genesys)
In the 1890s, a Clockwork Droid scanned the Twelfth Doctor, and listed organs they could harvest, as items on the menu at Mancini's Family Restaurant: liver, spleen, brain stem, eyes, lungs and skin. (TV: Deep Breath)
Alfred took the liver, kidneys and spleen of his first victim with the intention of using them to revive Julius Quilter when he died. (HOMEVID: Unnatural Selection)
The Seventh Doctor once claimed that megalomaniacs got that way from being forced to eat liver as children and thus getting too much vitamin A. (PROSE: Cat's Cradle: Witch Mark)
While being in the Kasaavin realm and talking to herself, the Thirteenth Doctor hoped that she was not inside a liver. She said that she hates being inside livers, since "people always get so offended". (TV: Spyfall)
Dorothy McShane had her liver function measured with a "sinister looking instrument" when she underwent a full medical examination to be a passenger on the Virgil. (PROSE: At Childhood's End)