Word Study
epithelium
CIDE DICTIONARY
epithelium, n. [NL., fr. Gr. 'epi` upon + nipple.].
The superficial layer of cells lining the alimentary canal and all its appendages, all glands and their ducts, blood vessels and lymphatics, serous cavities, etc. It often includes the epidermis (i. e. , keratin-producing epithelial cells), and it is sometimes restricted to the alimentary canal, the glands and their appendages, -- the term endothelium being applied to the lining membrane of the blood vessels, lymphatics, and serous cavities. [1913 Webster]
OXFORD DICTIONARY
epithelium, n. (pl. epitheliums or epithelia) the tissue forming the outer layer of the body surface and lining many hollow structures.
Derivative
epithelial adj.
Etymology
mod.L f. EPI- + Gk thele teat
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