(n.) A thin layer or fold of tissue, usually supported by a fibrous network, serving to cover or line some part or organ, and often secreting or absorbing certain fluids.

allantoic membrane amnion amniotic sac arachnoid membrane basement membrane coat coating collop conjuctiva covering cut deal disk eardrum feuille film flap foil fold hymen lamella lamina laminated glass laminated wood lap leaf maidenhead membrana serosa membrana tympana meninges meninx neurilemma pane panel patina peel pellicle pericardium perineurium plait plank plate plating pleura ply plywood rasher safety glass scum serosa sheet skin slab slat slice table tablet tympanic membrane tympanum velum veneer wafer