A porous membrane is a type of material that has tiny holes or spaces in it. These holes allow certain substances to pass through, while blocking others. It acts like a filter, letting some things go through while keeping others out. Full definition
Thinner or more porous membranes would be faster, which might aid dialysis, but they also could allow a greater number of unwanted molecules to slip through. (scientificamerican.com)
The device developed at FAU consists of one inlet for the injection of a raw unprocessed semen sample and two plastic chambers separated by porous membrane. (sciencedaily.com)
The gas was forced through a series of porous membranes with microscopic openings. (centrusenergy.com)