1. A reduction of atmospheric pressure: Deep-sea divers experience decompressions when the ocean causes an increased force on the body and, after returning to the surface of the ocean, because the air becomes normal again so their bodies can function in a proper way.
2. An operation to alleviate pressure on a bodily organ or some part of the body: After having severe pains in his back, the doctor made a diagnosis that Ned should have a surgical decompression therapy to the spinal chord to reduce the agony he was experiencing.
3. The process of decreasing the amount of pressure: Something was wrong with the air in the cabin of the aircraft and the plane had to be serviced again; especially, the decompression had to be controlled so the passengers would have proper air to breathe during the flight.
4. The procedure of enlarging information for the computer to its regular size so it can be deciphered by users: In the computer class at school, Jane learned that the process of decompression was significant in order to enable people to properly read the contents because an uncompressed digital image may require 20 megabytes; so, data compression is important in storing information digitally on computer disks and in transmitting it over communications networks; however, decompression provides better understanding.

An obstetric technique in which the abdomen is enclosed in a chamber which permits surrounding pressures to be controlled during the first stage of child labor: Abdominal decompression is intended to reduce pain and to shorten labor during the birth of a child.