What does decompression mean?
Decompression refers to the controlled release or reduction of pressure on something that has been compressed. Its most familiar use is in diving and aviation, where a person must undergo gradual decompression when returning to normal atmospheric pressure, since rapid change can cause nitrogen bubbles to form in the blood — a dangerous condition known as decompression sickness, or 'the bends'. In medicine, decompression describes surgical relief of pressure on nerves or other tissues, as in spinal decompression. In computing, it means converting compressed data back into its original form so files can be read or used. More loosely, the word also captures the idea of unwinding after sustained stress, as in taking time off work for decompression. Whether applied to bodies, data, or minds, the word conveys a careful return to a relaxed or expanded state.
nounThe process of returning to normal atmospheric pressure after being under increased pressure, or the gradual reduction of pressure on something. Also, the act or process of relieving compression or restoring something to its original, uncompressed state.
- The gradual reduction of ambient pressure on a body, especially when a diver or submarine occupant returns to the surface after being deep underwater.
- In computing: the restoration of compressed data to its original, uncompressed form.
- Relief from psychological or physical stress or tension; a period of relaxation after intense activity.
"Divers must ascend slowly to allow for safe decompression and avoid decompression sickness."
"After months of intense work, she took a quiet week at the coast as a period of decompression."
"The software performs automatic decompression of archived files when you open them."
Rarely used in the plural; typically appears only in technical or medical writing when distinguishing multiple distinct procedures or events.
"The patient underwent several spinal decompressions over the course of treatment."
The bends — decompression sickness — got their name because victims often doubled over in pain; without slow decompression, nitrogen bubbles form in a diver's blood like an opened soda going flat.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of decompression
Decompression derives from the Latin verb comprimere, meaning 'to press together', formed from com- ('together') and premere ('to press'). The English word compression appeared by the late 14th century, with decompression formed later by adding the prefix de-, indicating reversal. It gained prominence in the late 19th and early 20th centuries alongside the development of diving and aviation technology, where controlled pressure changes became a matter of life and death. Related words sharing the same Latin root include compress, depress, impression, and expression.
Related word forms
How decompression is actually used
Common in technical, medical, diving, aviation, and computing contexts. In informal usage it can describe unwinding after stress. The plural is rarely used except in technical contexts referring to multiple instances or types of the process.
Easily confused with decompression
Decompression refers to reducing pressure or expanding compressed data, while decomposition refers to the breakdown of matter into simpler substances.