Oysters are two small, round pieces of dark meat on the back of poultry near the thigh,^[1] in the hollow on the dorsal side of the ilium bone. The anatomical name of the muscle is iliotrochantericus caudalis.^[2]

In French, this part of the bird is called sot-l'y-laisse which translates, roughly, to "the fool leaves it there",^[3] as unskilled carvers sometimes accidentally leave it on the skeleton.