מלכים ב יח:כז פירוש: רש״י

To eat their own excrement. In the hunger [caused] by the siege.²⁰If they continue guarding the wall to prevent Ashur's army from entering, they will lay a prolonged siege to the city that will be so severe that the people will starve during the siege, causing them to “eat their own, etc.”—Ralbag

Their dung. Dung that is excreted through the orifice of the anus. Our Rabbis explained to euphemize and read, “צואתם” [instead of חריהם].²¹See Maseches Megillah 25b.

Their own urine. Loose excrement, the glands of the rectum, which is held by three glands. Alternatively, an expression of excrement which comes about through the chewing of the teeth [=שניהם].