en·do·derm / ˈendəˌdərm/ (also en·to·derm) • n. Zoology & Embryology the innermost layer of cells or tissue of an embryo in early development, or the parts derived from this, which include the lining of the gut and associated structures. Compare with ectoderm and mesoderm.DERIVATIVES: en·do·der·mal adj.en·do·der·mic adj.

endoderm (end-oh-derm) n. the inner of the three germ layers of the early embryo, which gives rise to the lining of most of the alimentary canal and its associated glands, the lining of the bronchi and alveoli of the lung, and most of the urinary tract.
—endodermal (en-doh-der-măl) adj.

endoderm (entoderm) The internal layer of cells of the gastrula, which will develop into the alimentary canal (gut) and digestive glands of the adult. See also germ layers.

endoderm In an embryo, the innermost layer of cells that gives rise to the lining of the archenteron (digestive cavity) and its associated glands. See also GASTRULATION.