Spleen

A spleen was an organ.

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 spleen, kidneys and liver of his first victim with the intention of using them to revive Julius Quilter when he died. (HOMEVID: Unnatural Selection)