Outer layer of a membrane

• The outer germ layer that develops into skin and nervous tissue
• Outer layer that's old, spurning new modern fashion

Wiktionary Word definitions in Wiktionary
n. 1 An outer layer of skin. 2 The outermost layer of cells in a developing embryo.

WordNet Word definitions in WordNet
n. the outer germ layer that develops into skin and nervous tissue [syn: ectoderm , ectoblast ]