The American Heritage® Dictionary of the English Language, 4th Edition
n. The layer of flat cells of mesodermal origin that lines the embryonic body cavity and gives rise to the squamous cells of the peritoneum, pericardium, and pleura.
n. A membrane of flat cells that lines the body cavity of embryos and forms the squamous cells of the peritoneum, pericardium, and pleura
the GNU version of the Collaborative International Dictionary of English
n. 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.
The Century Dictionary and Cyclopedia
n. The epithelium lining the entire primitive cœlom or body-cavity of the embryo; the cœlarium.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. epithelium originating in the embryonic mesoderm; lines the primordial body cavity
Word Usage
"The mesothelium is a membrane that covers and protects most of the internal organs of the body."