Bezoar: A clump or wad of swallowed food or hair. Bezoars can block the digestive system, especially the exit of the stomach. A bezoar composed of hair is called a trichobezoar. A bezoar composed of vegetable materials is called a phytobezoar. A bezoar composed of hair and food is called a trichophytobezoar. Rapunzel syndrome is the name that has been used to refer to a condition in which the intestinal tract is blocked by a trichobezoar due to swallowing one's own hair.