1) Animal tissue 
• (a.) Of or pertaining to epithelium; as, epithelial cells; epithelial cancer.
Refers to the cells that line the internal and external surfaces of the body.
An epithelial tissue is a tissue that covers the external surface of the body and lines hollow structures inside the body. Related entry • epithelium
Pertaining to or composed of epithelium. ... (16 Dec 1997) ... 
(ep″ĭ-the´le-әl) pertaining to or composed of epithelium.
Ep`i·the'li·al adjective Of or pertaining to epithelium; as, epithelial cells; epithelial cancer. 
Relating to or composed of epithelium.
Type: Term Pronunciation: ep′i-thē′lē-ăl Definitions: 1. Relating to or consisting of epithelium.
Epithelial: Relating to the epithelium, the outside layer of cells that covers all the free, open surfaces of the body including the skin, and mucous membranes that communicate with the outside of the body.
The cell linings covering most of the internal and external surface of the body and its organs.
[adj] - of or belonging to the epithelium
adjective of or belonging to the epithelium; `epithelial layer`
of or pertaining to the epithelium e.g. epithelial cells.