membrane
n. countablen. a thin layer of material that acts like a skin. It can cover parts of the body or let certain things pass through while blocking others.
n. a thin, pliable layer of tissue that covers or lines an organ or cell, or a synthetic material acting as a selective barrier.
The cell membrane protects the inside of the cell.
The waterproof jacket uses a special membrane that lets sweat out but keeps rain from getting in.
In biological systems, the semi-permeable membrane is essential for maintaining homeostasis by regulating the transport of ions and molecules between the internal and external environments.
Late Middle English, borrowed from Latin membrāna (“skin or membrane that covers parts of the body”), from membrum (“a limb or member of the body”) + -āna. Doublet of membrana.
Often used with 'semi-permeable' or 'porous' in scientific contexts.