MESOTHELIUM

‖Mes′o‐the″li‐um (?), n. [[NL., fr. Gr. μέσοσ middle + E. epithelium.]] (Biol.) Epithelial mesoderm; a layer of cuboidal epithelium cells, formed from a portion of the mesoderm during the differetiation of the germ layers. It constitutes the boundary of the cœlum.