/ ˈmembreɪn; NAmE / noun [ C , U ]
1.
a thin layer of skin or tissue that connects or covers parts inside the body
—see also mucous membrane
2.
a very thin layer found in the structure of cells in plants
3.
a thin layer of material used to prevent air, liquid, etc. from entering a particular part of sth :
a waterproof membrane
► mem·bran·ous / ˈmembrənəs; NAmE / adjective
••
WORD ORIGIN
late Middle English : from Latin membrana , from membrum limb.