semipermeable membrane

Definitions of semipermeable membrane

1. noun

   a membrane (as a cell membrane) that allows some molecules to pass through but not others
   types:

   cell membrane, cytomembrane, plasma membrane

   a thin membrane (a double layer of lipids) enclosing the cytoplasm of a cell; proteins in the membrane control passage of ions (like sodium or potassium or calcium) in and out of the cell

   type of:

   membrane, tissue layer

   a pliable sheet of tissue that covers or lines or connects the organs or cells of animals or plants