2.The reduction of atmospheric pressure experienced by divers rising from deep water to the surface, thus reducing the concentration of dissolved atmospheric gases in the blood; especially applied to a gradual reduction of such pressure.
3.The process, analogous to sense 2, undergone by divers in a decompression chamber, in which an artificially high atmospheric pressure is gradually lowered to normal pressure.
4.A return to a normal, more relaxed state after a period of intense stress, psychological pressure, or urgent activity; of people.