Sweetbreads or ris are culinary names for the thymus or the pancreas glands especially of the calf (ris de veau) and lamb (ris d'agneau) (although beef and pork sweetbreads are also eaten).
Various other glands used as food have also been called 'sweetbreads', including the parotid gland, the sublingual glands, and testicles (cf. Rocky Mountain oyster). The "heart" sweetbreads are more spherical in shape, and surrounded symmetrically by the "throat" sweetbreads, which are more cylindrical in shape.