təˈpēd.əm noun
( plural tape·ta -d.ə)
Etymology: New Latin, from Latin tapete carpet, tapestry, from Greek tapēt-, tapēs carpet, rug — more at tapestry
1. : the layer of nutritive cells that invests the sporogenous tissue in the sporangium of higher plants and that is broken down and digested during development of the spores
2.
a. : any of various membranous layers or areas especially of the choroid and retina of the eye ; specifically : a layer in the choroid chiefly of nocturnal mammals that reflects light and is made up of several layers of flattened cells covered by a zone of double refracting crystals
b. : a layer of nerve fibers derived from the corpus callosum and forming part of the roof of each lateral ventricle of the brain — called also tapetum lu·ci·dum -ˈlüsə̇dəm