epithelium /-thē″lē·əm/ [Gk, epi + thele, nipple] , the covering of the internal and external organs of the body and the lining of vessels, body cavities, glands, and organs. It consists of cells bound together by connective material and varies in the number of layers and the kinds of cells. The stratified squamous epithelium of the epidermis comprises five different cellular layers. −epithelial, adj.
