compression

American  

[kuhm-presh-uhn] / kəmˈprɛʃ ən /

Rarely compressure

noun

1. the act of compressing.

   When performing CPR, give 30 chest compressions at a rate of 100 to 120 compressions per minute.

2. the state of being compressed, or the effect, result, or consequence of being compressed.

   Compression of the nerves can lead to tingling and numbness farther down the arm.

3. (in internal-combustion engines) the reduction in volume and increase of pressure of the air or combustible mixture in the cylinder prior to ignition, produced by the motion of the piston toward the cylinder head after intake.

4. Also called data compression.  Computers. reduction of the storage space required for data by changing its format.

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adjective

1. Computers. relating to the process of reducing the storage space required for data by changing its format.

   Experiments show that this approach can effectively improve the compression ratio of existing codes.

2. being or relating to a type of medical garment that provides pressure and support, reduces swelling, promotes circulation, holds tissue in place, etc..

   Ask your doctor if compression stockings would help the swelling in your legs.

   After surgery, it may be necessary to wear a compression garment.

   Compression sleeves are an important part of lymphedema management.

compression British  

/ kəmˈprɛʃən /

noun

1. Also called: compressure.  the act of compressing or the condition of being compressed

2. an increase in pressure of the charge in an engine or compressor obtained by reducing its volume

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compression Scientific  

/ kəm-prĕsh′ən /

1. A force that tends to shorten or squeeze something, decreasing its volume.

2. The degree to which a substance has decreased in size (in volume, length, or some other dimension) after being or while being subject to stress.

3. See also strain

4. The re-encoding of data (usually the binary data used by computers) into a form that uses fewer bits of information than the original data. Compression is often used to speed the transmission of data such as text or visual images, or to minimize the memory resources needed to store such data.

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compression Cultural  

1. See data compression.

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Other Word Forms

• compressional adjective
• noncompression noun
• overcompression noun
• precompression noun
• supercompression noun

Etymology

Origin of compression

First recorded in 1350–1400; Middle English, from Anglo-French, from Latin compressiōn-, stem of compressiō; equivalent to compress + -ion

Explanation

Whenever something is squished together, compression takes place, like a tight bandage around your sprained ankle — the compression helps protect it from further injury. Compression comes from the Latin word compressare, meaning “to press together.” Compression is an important part of how car engines function: fuel and air are compressed then ignited and that makes the power that turns the wheels. Compression can also happen to your day's schedule, such as when a snow storm causes school to start late, a schedule compression means that you have all your classes but they are shorter.

Example Sentences

Think fewer ripped bodices, more compression socks — and all the sweeter for it.

From Los Angeles Times • Apr. 9, 2026

However, the bank’s net interest margin remains crucial for profitability and the analysts expect a 23bp on-year compression in 2026 NIM on lower asset yields.

From The Wall Street Journal • Apr. 6, 2026

The internet called it “Pied Piper,” after the fictional compression algorithm in HBO’s “Silicon Valley” series.

From MarketWatch • Apr. 6, 2026

The compression algorithm reduced “key value memory size” in artificial-intelligence models by at least six times and lifted speeds up to eightfold, without compromising model accuracy, Google researchers said.

From Barron's • Apr. 2, 2026

Both are employed in European technology, but the former is more common—the arch is a classic example of compression.

From "1491" by Charles C. Mann