A membrane is a thin LAYER of tissue that covers the surface of an organism or organ. The crossword solutions for the term membrane include 'LAYER' (5 letters), 'SKIN' (4 letters), 'FILM' (4 letters), 'tela' (4 letters), 'sclera' (6 letters), 'caul' (4 letters), and 'WEB' (3 letters). 'Serosa' (6 letters) is also a term used to describe a membrane, which is a serous membrane that lines the walls of certain body cavities. All of these terms refer to a thin LAYER of tissue that serves as a barrier between two environments.