noun
Technical term in chemistry and engineering for a water purification method that uses a semipermeable membrane to remove ions and molecules.
逆浸透法は海水淡水化に広く使われている。
Reverse osmosis is widely used for seawater desalination.
浸透 means 'osmosis' or 'permeation'; 逆浸透法 is the method of applying pressure to reverse the natural osmotic flow.
Compound of 逆 (reverse) + 浸透 (osmosis) + 法 (method). A calque from English 'reverse osmosis'.